| /* EightThirtyTwo backend for vbcc, |
| based on the generic RISC backend |
| |
| The CPU targeted by this backend, and the latest version, can be found at |
| https://github.com/robinsonb5/EightThirtyTwo |
| |
| */ |
| |
| // DONE - T2 no longer used at all - frees up a register for the main code generator |
| |
| // DONE Update the memcpy code to save/allocate registers if needed. |
| // DONE Update the div code likewise. |
| |
| // Complete the work on object tracking. In particular take care of tracking an object vs |
| // its address. |
| // Also track via addressing-mode analysis whether or not it's valuable to save a value; |
| // Values can also be saved to otherwise unused registers. (The compiler is almost certainly |
| // already smart enough to make use of unused registers for this, however!) |
| |
| // DONE: eliminate unnecessary register shuffling for compare. |
| |
| // DONE: Implement block copying |
| |
| // DONE: Implement division / modulo using library code. |
| // DONE: Mark registers as disposable if their contents are never used beyond the current op. |
| |
| // Look at ways of improving code efficiency. Look for situations where the output of one IC |
| // becomes the input of another? Would make a big difference when registers are all in use. |
| |
| // Minus could be optimised for the in-register case. |
| |
| // DONE: Do we need to reserve two temp registers? Turns out one was sufficient, and giving |
| // the code generator an extra one to play with helped a great deal. |
| |
| // Restrict byte and halfword storage to static and extern types, not stack-based variables. |
| // (Having learned more, bytes and halfwords on the stack are fine, the complication is with |
| // function parameters, which are promoted to int - thus the size modifier will be different |
| // for parameters and local variables even though both live on the stack.) |
| |
| // DONE - Avoid moving registers for cmp and test when possible. |
| |
| // Condition code for test may well be already set by previous load. |
| // Done for TEST, do the same for comparisons? |
| |
| // Deal with dereferencing in temp caching - can we avoid repeated setups in tmp, maybe using r0? |
| |
| |
| #include "supp.h" |
| |
| #define DBGMSG 1 |
| |
| static char FILE_[] = __FILE__; |
| |
| /* Public data that MUST be there. */ |
| |
| /* Name and copyright. */ |
| char cg_copyright[] = |
| "vbcc EightThirtyTwo code-generator, (c) 2019/2020 by Alastair M. Robinson\nBased on the generic RISC example backend (c) 2001 by Volker Barthelmann"; |
| |
| /* Commandline-flags the code-generator accepts: |
| 0: just a flag |
| VALFLAG: a value must be specified |
| STRINGFLAG: a string can be specified |
| FUNCFLAG: a function will be called |
| apart from FUNCFLAG, all other versions can only be specified once */ |
| int g_flags[MAXGF] = { 0 }; |
| |
| #define FLAG_PIC 0 |
| #define FLAG_LE 1 |
| #define FLAG_BE 2 |
| |
| /* the flag-name, do not use names beginning with l, L, I, D or U, because |
| they collide with the frontend */ |
| /* 832-specific flags, "fpic" enables position independent code - name chosen to match gcc */ |
| char *g_flags_name[MAXGF] = { "fpic","el","eb" }; |
| |
| char flag_832_bigendian; |
| |
| /* the results of parsing the command-line-flags will be stored here */ |
| union ppi g_flags_val[MAXGF] = { 0,0,0 }; |
| |
| /* Alignment-requirements for all types in bytes. */ |
| zmax align[MAX_TYPE + 1]; |
| |
| /* Alignment that is sufficient for every object. */ |
| zmax maxalign; |
| |
| /* CHAR_BIT for the target machine. */ |
| zmax char_bit; |
| |
| /* sizes of the basic types (in bytes) */ |
| zmax sizetab[MAX_TYPE + 1]; |
| |
| /* Minimum and Maximum values each type can have. */ |
| /* Must be initialized in init_cg(). */ |
| zmax t_min[MAX_TYPE + 1]; |
| zumax t_max[MAX_TYPE + 1]; |
| zumax tu_max[MAX_TYPE + 1]; |
| |
| /* Names of all registers. will be initialized in init_cg(), |
| register number 0 is invalid, valid registers start at 1 */ |
| char *regnames[MAXR + 1]; |
| |
| /* The Size of each register in bytes. */ |
| zmax regsize[MAXR + 1]; |
| |
| /* a type which can store each register. */ |
| struct Typ *regtype[MAXR + 1]; |
| |
| /* regsa[reg]!=0 if a certain register is allocated and should */ |
| /* not be used by the compiler pass. */ |
| int regsa[MAXR + 1]; |
| |
| /* Specifies which registers may be scratched by functions. */ |
| int regscratch[MAXR + 1]; |
| |
| /* specifies the priority for the register-allocator, if the same |
| estimated cost-saving can be obtained by several registers, the |
| one with the highest priority will be used */ |
| int reg_prio[MAXR + 1]; |
| |
| /* an empty reg-handle representing initial state */ |
| struct reg_handle empty_reg_handle = { 0, 0 }; |
| |
| /* Names of target-specific variable attributes. */ |
| char *g_attr_name[] = { "__interrupt", "__ctor", "__dtor", "__weak", 0 }; |
| |
| /****************************************/ |
| /* Private data and functions. */ |
| /****************************************/ |
| |
| #define USE_COMMONS 0 |
| |
| /* alignment of basic data-types, used to initialize align[] */ |
| /* In actual fact 832 has full load/store alignment so this is negotiable based on -speed / -size flags. */ |
| static long malign[MAX_TYPE + 1] = { 1, 1, 2, 4, 4, 4, 4, 8, 8, 1, 4, 1, 1, 1, 4, 1 }; |
| |
| /* sizes of basic data-types, used to initialize sizetab[] */ |
| static long msizetab[MAX_TYPE + 1] = { 1, 1, 2, 4, 4, 8, 4, 8, 8, 0, 4, 0, 0, 0, 4, 0 }; |
| |
| /* used to initialize regtyp[] */ |
| static struct Typ ltyp = { LONG }, ldbl = { |
| DOUBLE}, lchar = { |
| CHAR}; |
| |
| /* macros defined by the backend */ |
| static char *marray[] = { "__section(x)=__vattr(\"section(\"#x\")\")", |
| "__EIGHTTHIRTYTWO__", |
| "__constructor(pri)=__vattr(\"ctor(\"#pri\")\")", |
| "__destructor(pri)=__vattr(\"dtor(\"#pri\")\")", |
| "__weak=__vattr(\"weak\")", |
| 0 |
| }; |
| |
| /* special registers */ |
| static int pc; /* Program counter */ |
| static int sp; /* Stackpointer */ |
| static int tmp; |
| static int t1, t2; /* temporary gprs */ |
| static int f1, f2, f3; /* temporary fprs */ |
| static int loopid = 0; /* must be unique for every function in a compilation unit */ |
| |
| |
| /* sections */ |
| #define DATA 0 |
| #define BSS 1 |
| #define CODE 2 |
| #define RODATA 3 |
| #define SPECIAL 4 |
| |
| //static long stack; |
| static int section = -1, newobj; |
| static char *codename = "\t.section\t.text"; |
| static char *dataname = "\t.section\t.data"; |
| static char *bssname = "\t.section\t.bss"; |
| static char *rodataname = "\t.section\t.rodata"; |
| static int sectionid=0; |
| |
| /* assembly-prefixes for labels and external identifiers */ |
| static char *labprefix = "l", *idprefix = "_"; |
| |
| /* variables to keep track of the current stack-offset in the case of |
| a moving stack-pointer */ |
| static long pushed; |
| static long notyetpopped; |
| |
| static long localsize, rsavesize, argsize; |
| |
| static int count_constantchunks(zmax v); |
| static void emit_constanttotemp(FILE * f, zmax v); |
| static void emit_statictotemp(FILE * f, char *lab, int suffix, int offset); |
| static void emit_externtotemp(FILE * f, char *lab, int offset); |
| static void emit_pcreltotemp2(FILE *f,struct obj *p); |
| |
| static void emit_prepobj(FILE * f, struct obj *p, int t, int reg, int offset); |
| static int emit_objtoreg(FILE * f, struct obj *p, int t,int reg); |
| |
| /* calculate the actual current offset of an object relativ to the |
| stack-pointer; we use a layout like this: |
| ------------------------------------------------ |
| | arguments to this function | |
| ------------------------------------------------ |
| | return-address [size=4] | |
| ------------------------------------------------ |
| | caller-save registers [size=rsavesize] | |
| ------------------------------------------------ |
| | local variables [size=localsize] | |
| ------------------------------------------------ |
| | arguments to called functions [size=argsize] | |
| ------------------------------------------------ |
| All sizes will be aligned as necessary. |
| For a moving stack-pointer, the stack-pointer will usually point |
| to the bottom of the area for local variables, but will move while |
| arguments are put on the stack. |
| |
| This is just an example layout. Other layouts are also possible. |
| */ |
| |
| static long real_offset(struct obj *o) |
| { |
| long off = 0; |
| if((o->flags&VAR) && isauto(o->v->storage_class)) |
| off=zm2l(o->v->offset); |
| // printf("Parameter offset: %d, localsize: %d, rsavesize: %d\n",off,localsize,rsavesize); |
| if (off < 0) { |
| /* function parameter */ |
| off = localsize + rsavesize + 4 - off - zm2l(maxalign); |
| } |
| off += pushed; |
| off += notyetpopped; |
| off += zm2l(o->val.vmax); |
| return off; |
| } |
| |
| |
| static int isstackparam(struct obj *o) |
| { |
| int result=0; |
| // if(o->flags&VAR && o->flags® && o->reg==sp) |
| // if(o->flags&(VAR|DREFOBJ)==VAR) |
| if((o->flags&VAR) && !(o->flags®)) |
| { |
| if(isauto(o->v->storage_class)) |
| { |
| long off = zm2l(o->v->offset); |
| if (off < 0) |
| result=1; |
| } |
| } |
| return(result); |
| } |
| |
| /* Convenience function to determine whether we're assigning to 0(r6) |
| and can thus use a more efficient writing sequence. */ |
| |
| int istopstackslot(struct obj *o) |
| { |
| if(!o) |
| return(0); |
| if((o->flags&(VAR|REG|DREFOBJ))==VAR && o->v) |
| { |
| if(isauto(o->v->storage_class) |
| && real_offset(o)==0) |
| return(1); |
| } |
| return(0); |
| } |
| |
| /* changes to a special section, used for __section() */ |
| static int special_section(FILE * f, struct Var *v) |
| { |
| char *sec; |
| if (!v->vattr) |
| return 0; |
| sec = strstr(v->vattr, "section("); |
| if (!sec) |
| return 0; |
| sec += strlen("section("); |
| emit(f, "\t.section\t"); |
| while (*sec && *sec != ')') |
| emit_char(f, *sec++); |
| emit(f, "\n"); |
| if (f) |
| section = SPECIAL; |
| return 1; |
| } |
| |
| /* Returns 1 if the symbol has weak linkage */ |
| static int isweak(struct Var *v) |
| { |
| if (!v->vattr) |
| return 0; |
| if (strstr(v->vattr, "weak")) |
| return (1); |
| return 0; |
| } |
| |
| /* Emits a pointer to a function in a .ctor or .dtor section for automatic setup/cleanup */ |
| static int ctor_dtor(FILE * f, struct Var *v) |
| { |
| int dtor = 0; |
| char *sec; |
| if (!v->vattr) |
| return 0; |
| sec = strstr(v->vattr, "ctor("); |
| if (!sec) { |
| dtor = 1; |
| sec = strstr(v->vattr, "dtor("); |
| } |
| if (!sec) |
| return 0; |
| sec += strlen("ctor("); |
| emit(f, "\t%s.", dtor ? ".dtor .dtor" : ".ctor .ctor"); |
| while (*sec && *sec != ')') |
| emit_char(f, *sec++); |
| emit(f, "\n\t.ref\t%s%s\n", idprefix, v->identifier); |
| |
| return 1; |
| } |
| |
| |
| #define TEMP_TMP 0 |
| #define TEMP_T1 1 |
| struct tempobj |
| { |
| struct obj o; |
| int reg; |
| }; |
| struct tempobj tempobjs[2]; |
| |
| void cleartempobj(FILE *f, int reg) |
| { |
| int i; |
| if(reg==tmp) i=TEMP_TMP; |
| else if(reg==t1) i=TEMP_T1; |
| else return; |
| // emit(f,"// clearing %s\n",regnames[reg]); |
| |
| tempobjs[i].reg=0; |
| } |
| |
| void settempkonst(FILE *f,int reg,int v) |
| { |
| int i; |
| if(reg==tmp) i=TEMP_TMP; |
| else if(reg==t1) i=TEMP_T1; |
| else return; |
| tempobjs[i].reg=reg; |
| tempobjs[i].o.flags=KONST; |
| tempobjs[i].o.val.vlong=v; |
| // emit(f,"// set %s to konst %d\n",regnames[reg],v); |
| } |
| |
| |
| // Add an adjustment due to postinc / predec to a cached object |
| void adjtempobj(FILE *f,int reg,int offset) |
| { |
| if(reg<=1) |
| tempobjs[reg].o.val.vlong+=offset; |
| } |
| |
| |
| // Store any passing value in tempobj records for optimisation. |
| // FIXME - need to figure out VARADR semantics for stored objects. |
| void settempobj(FILE *f,int reg,struct obj *o,int offset,int varadr) |
| { |
| int i; |
| if(reg==tmp) i=TEMP_TMP; |
| else if(reg==t1) i=TEMP_T1; |
| else return; |
| // if(reg==t1) |
| // emit(f,"// Setting %s to %x (%x)\n",regnames[reg],o,o->v); |
| tempobjs[i].reg=reg; |
| tempobjs[i].o=*o; |
| tempobjs[i].o.val.vlong+=offset; // Account for any postinc / predec |
| if(varadr) |
| tempobjs[i].o.flags|=VARADR; |
| } |
| |
| |
| // Compare a pair of struct obj* for equivalence. |
| // The first object should be the "live" object, the second one the cached object." |
| int matchobj(FILE *f,struct obj *o1,struct obj *o2,int varadr) |
| { |
| int result=1; |
| int flg=o1->flags; |
| if(varadr) |
| flg|=VARADR; |
| // emit(f,"// comparing flags %x with %x\n",o1->flags, o2->flags); |
| // if((o1->flags&~VARADR)!=(o2->flags&~VARADR)) |
| // FIXME - need to figure out VARADR semantics for stored objects. |
| emit(f,"\t\t\t\t\t\t// matchobj comparing flags %d with %d\n",flg,o2->flags); |
| if(flg!=(o2->flags)) |
| return(0); |
| |
| // emit(f,"// comparing regs %d with %d\n",o1->reg, o2->reg); |
| // If the register-based value is being dereferenced we would have to track |
| // the register itself being updated. Unless the value's in tmp using a cached |
| // version isn't a win anyway. |
| if((o1->flags&(REG|DREFOBJ)==REG) && (o1->reg==o2->reg)) |
| return(1); |
| |
| if(o1->flags&KONST) |
| { |
| // emit(f,"\t\t\t\t\t\t// Comparing constants %x with %x\n",o1->val.vlong,o2->val.vlong); |
| if(o1->val.vlong == o2->val.vlong) |
| return(1); |
| else |
| { // Attempt fuzzy matching... |
| int d=o1->val.vlong-o2->val.vlong; |
| // Don't bother if we need fewer than four LIs to represent the value, or if we'd need more than 1 LI for the offset. |
| if(count_constantchunks(o1->val.vlong)<4 || count_constantchunks(d)>1) |
| { |
| // emit(f,"\t\t\t\t\t\t// Gains from fuzzy matching too small, ignoring.\n"); |
| return(0); |
| } |
| else |
| return(2); |
| } |
| } |
| |
| if(!(o1->flags&VAR)) |
| return(0); // Not a var? Can't do any more. |
| |
| if(o1->v==0 || o2->v==0) |
| return(0); |
| |
| if(o1->v == o2->v && o1->val.vlong == o2->val.vlong) |
| return(1); |
| |
| if(!(flg&VARADR)) |
| return(0); // Can only attempt fuzzy matching if this is a varadr |
| |
| if(isauto(o1->v->storage_class) && isauto(o2->v->storage_class)) |
| { |
| if(DBGMSG) |
| emit(f,"\t\t\t\t\t\t//auto: flags: %x, comparing %d, %d with %d, %d\n", |
| flg,o1->v->offset,o1->val.vlong, o2->v->offset,o2->val.vlong); |
| // Can't fuzzy match between parameters and vars on stack |
| if((o1->v->offset<0 && o2->v->offset>=0) || (o1->v->offset>=0 && o2->v->offset<0)) |
| return(0); |
| if(o1->v->offset==o2->v->offset && o1->val.vlong==o2->val.vlong) |
| return(1); |
| if((o1->flags&DREFOBJ) || (o2->flags&DREFOBJ)) // Can't fuzzy match if we're dereferencing. |
| return(0); |
| return(2); |
| } |
| |
| if(isextern(o1->v->storage_class) && isextern(o2->v->storage_class)) |
| { |
| if(DBGMSG) |
| emit(f,"\t\t\t\t\t\t//extern: comparing %d with %d\n",o1->val.vlong, o2->val.vlong); |
| if(strcmp(o1->v->identifier,o2->v->identifier)) |
| return(0); |
| if(o1->val.vlong==o2->val.vlong) |
| return(1); |
| if((o1->flags&DREFOBJ) || (o2->flags&DREFOBJ)) // Can't fuzzy match if we're dereferencing. |
| return(0); |
| return(2); |
| } |
| |
| return(0); |
| } |
| |
| |
| int matchoffset(struct obj *o,struct obj *o2) |
| { |
| if(o->flags&KONST) |
| return(o->val.vlong-o2->val.vlong); |
| if(isextern(o->v->storage_class)) |
| return(o->val.vlong-o2->val.vlong); |
| if(isauto(o->v->storage_class)) |
| // return((o->val.vlong+real_offset(o))-(o2->val.vlong+real_offset(o2))); |
| return((o->val.vlong+o->v->offset)-(o2->val.vlong+o2->v->offset)); |
| return(0); |
| } |
| |
| |
| void obsoletetempobj(FILE *f,int reg,struct obj *o,int varadr) |
| { |
| // emit(f,"\t\t\t\t\t// Attempting to obsolete obj\n"); |
| if(tempobjs[0].reg==reg && matchobj(f,o,&tempobjs[0].o,varadr)) |
| { |
| emit(f,"\t\t\t\t\t\t// Obsoleting tmp\n"); |
| cleartempobj(f,tmp); |
| } |
| if(tempobjs[1].reg==reg && matchobj(f,o,&tempobjs[0].o,varadr)) |
| { |
| emit(f,"\t\t\t\t\t\t// Obsoleting t1\n"); |
| cleartempobj(f,t1); |
| } |
| } |
| |
| |
| // Check the tempobj records to see if the value we're interested in can be found in either. |
| int matchtempobj(FILE *f,struct obj *o,int varadr,int preferredreg) |
| { |
| int hit=0; // Hit will be 1 for an exact match, 2 for a near miss. |
| // return(0); // Temporarily disable matching |
| if(tempobjs[0].reg && (hit=matchobj(f,o,&tempobjs[0].o,varadr))) |
| { |
| // emit(f,"//match found - tmp\n"); |
| // printf("//match found - tmp\n"); |
| if(hit==1) |
| return(tempobjs[0].reg); |
| else if(hit==2) |
| { |
| int offset=matchoffset(o,&tempobjs[0].o); |
| emit(f,"\t\t\t\t\t\t// Fuzzy match found against tmp.\n"); |
| if(preferredreg==tmp) |
| { |
| emit(f,"\tmr\t%s\n",regnames[t1]); |
| emit(f,"\t.liconst\t%d\n",offset); |
| emit(f,"\taddt\t%s\n",regnames[t1]); |
| settempobj(f,t1,&tempobjs[0].o,0,0); |
| settempobj(f,tmp,o,0,varadr); |
| } |
| else |
| { |
| emit(f,"\tmr\t%s\n",regnames[preferredreg]); |
| emit(f,"\t.liconst\t%d\n",offset); |
| settempkonst(f,tmp,offset); |
| emit(f,"\tadd\t%s\n",regnames[preferredreg]); |
| settempobj(f,preferredreg,o,0,varadr); |
| } |
| return(preferredreg); |
| // return(tempobjs[0].reg); |
| } |
| else |
| return(0); |
| } |
| else if(tempobjs[1].reg && (hit=matchobj(f,o,&tempobjs[1].o,varadr))) |
| { |
| // Temporarily disable t1 matching. FIXME - keep t1 records more up-to-date. |
| // return(0); |
| // emit(f,"//match found - t1\n"); |
| // printf("//match found - t1\n"); |
| if(hit==1) |
| return(tempobjs[1].reg); |
| else if(hit==2) |
| { |
| int offset=matchoffset(o,&tempobjs[1].o); |
| if(DBGMSG) |
| emit(f,"\t\t\t\t\t\t//Fuzzy match found, offset: %d (varadr: %d)\n",offset,varadr); |
| // Fuzzy match against t1 - if target is t1 use add, otherwise use addt. |
| emit(f,"\t.liconst\t%d\n",offset); |
| if(preferredreg!=tempobjs[1].reg) |
| { |
| emit(f,"\taddt\t%s\n",regnames[tempobjs[1].reg]); |
| if(preferredreg!=tmp) |
| emit(f,"\tmr\t%s\n",regnames[preferredreg]); |
| settempobj(f,tmp,o,0,0); |
| settempobj(f,preferredreg,o,0,varadr); |
| } |
| else |
| { |
| emit(f,"\tadd\t%s\n",regnames[tempobjs[1].reg]); |
| settempkonst(f,tmp,offset); |
| settempobj(f,tempobjs[1].reg,o,0,varadr); |
| } |
| return(preferredreg); |
| } |
| return(0); |
| } |
| else |
| return(0); |
| } |
| |
| |
| int matchtempkonst(FILE *f,int k,int preferredreg) |
| { |
| // return(0); // Temporarily disable matching |
| struct obj o; |
| o.flags=KONST; |
| o.val.vlong=k; |
| return(matchtempobj(f,&o,0,preferredreg)); |
| } |
| |
| |
| /* Generates code to store register r into memory object o. */ |
| |
| static void store_reg(FILE * f, int r, struct obj *o, int type) |
| { |
| // Need to take different types into account here. |
| if(DBGMSG) |
| emit(f, "\t\t\t\t\t\t// Store_reg to type 0x%x, flags 0x%x\n", type,o->flags); |
| |
| type &= NQ; // Filter out unsigned, etc. |
| if((type==CHAR || type==SHORT) && isstackparam(o)) |
| { |
| emit(f, "\t\t\t\t\t\t// Promoting storage size of stack parameter to int\n"); |
| type=INT; |
| } |
| |
| switch (type) { |
| case CHAR: |
| emit_prepobj(f, o, type & NQ, tmp, 0); |
| emit(f, "\texg\t%s\n", regnames[r]); |
| emit(f, "\tstbinc\t%s\t//WARNING - pointer / reg not restored, might cause trouble!\n", regnames[r]); |
| cleartempobj(f,tmp); |
| cleartempobj(f,r); |
| break; |
| case SHORT: |
| emit_prepobj(f, o, type & NQ, tmp, 0); |
| emit(f, "\texg\t%s\n", regnames[r]); |
| emit(f, "\thlf\n\tst\t%s\n", regnames[r]); |
| cleartempobj(f,tmp); |
| cleartempobj(f,r); |
| break; |
| case INT: |
| case LONG: |
| case POINTER: |
| // if o is a reg, can store directly. |
| if ((o->flags & (REG | DREFOBJ)) == (REG | DREFOBJ)) { |
| emit(f, "\tmt\t%s\n", regnames[r]); |
| emit(f, "\tst\t%s\n", regnames[o->reg]); |
| // settempobj(f,r,o,0,0); |
| if((type&NQ)!=INT || (type & VOLATILE) || (type & PVOLATILE)) |
| { |
| emit(f,"\t// Volatile, or not int - not caching\n"); |
| cleartempobj(f,r); |
| } |
| else |
| settempobj(f,r,o,0,0); // FIXME - is this correct? |
| settempobj(f,tmp,o,0,0); // FIXME - is this correct? |
| } else { |
| if(o->flags & DREFOBJ) { // Can't use the offset / stmpdec trick for dereferenced objects. |
| // FIXME, not strictly true - could use it for dereferenced constants |
| emit_prepobj(f, o, type & NQ, tmp, 0); |
| emit(f, "\texg\t%s\n", regnames[r]); |
| emit(f, "\tst\t%s\n", regnames[r]); |
| if(r==t1 || (o->am && o->am->disposable)) |
| emit(f, "\t\t\t\t\t\t// WARNING - Object is disposable, not bothering to undo exg - check correctness\n"); |
| else |
| emit(f, "\texg\t%s\n", regnames[r]); |
| cleartempobj(f,tmp); |
| cleartempobj(f,r); |
| } |
| else { |
| emit_prepobj(f, o, type & NQ, tmp, 4); // stmpdec predecrements, so need to add 4! |
| emit(f, "\tstmpdec\t%s\n \t\t\t\t\t\t// WARNING - check that 4 has been added.\n", regnames[r]); |
| adjtempobj(f,tmp,-4); |
| // cleartempobj(f,tmp); |
| if((type&NQ)!=INT || (type & VOLATILE) || (type & PVOLATILE)) |
| { |
| emit(f,"\t// Volatile, or not int - not caching\n"); |
| cleartempobj(f,r); |
| } |
| else |
| settempobj(f,r,o,0,0); // FIXME - is this correct? |
| } |
| } |
| break; |
| case LLONG: |
| if ((o->flags & (REG | DREFOBJ)) == (REG | DREFOBJ)) { |
| emit_prepobj(f, o, type & NQ, tmp, 0); |
| printf("store_reg: storing long long to dereferenced register\n"); |
| emit(f,"//FIXME - need to store 64-bits\n"); |
| ierror(0); |
| } |
| else { |
| // |
| printf("store_reg: storing long long in %s to reg\n",regnames[r]); |
| ierror(0); |
| } |
| break; |
| default: |
| printf("store_reg: unhandled type 0x%x\n", type); |
| ierror(0); |
| break; |
| } |
| } |
| |
| |
| /* Yields log2(x)+1 or 0. */ |
| static long pof2(zumax x) |
| { |
| zumax p; |
| int ln = 1; |
| p = ul2zum(1L); |
| while (ln <= 32 && zumleq(p, x)) { |
| if (zumeqto(x, p)) |
| return ln; |
| ln++; |
| p = zumadd(p, p); |
| } |
| return 0; |
| } |
| |
| |
| static int availreg() |
| { |
| int i; |
| for(i=FIRST_GPR+RESERVED_GPRS;i<(LAST_GPR-1);++i) |
| if(regs[i]==0) |
| return(i); |
| return(0); |
| } |
| |
| |
| static struct IC *preload(FILE *, struct IC *,int stacksubst); |
| |
| static void function_top(FILE *, struct Var *, long); |
| static int function_bottom(FILE * f, struct Var *, long,int); |
| |
| #define isreg(x) ((p->x.flags&(REG|DREFOBJ))==REG) |
| #define involvesreg(x) ((p->x.flags&(REG))==REG) |
| #define isconst(x) ((p->x.flags&(KONST|DREFOBJ))==KONST) |
| |
| static int q1reg, q2reg, zreg; |
| |
| static char *ccs[] = { "EQ", "NEQ", "SLT", "GE", "LE", "SGT", "EX", "" }; |
| static char *logicals[] = { "or", "xor", "and" }; |
| |
| static char *arithmetics[] = { "shl", "shr", "add", "sub", "mul", "(div)", "(mod)" }; |
| |
| /* Does some pre-processing like fetching operands from memory to |
| registers etc. */ |
| static struct IC *preload(FILE * f, struct IC *p,int stacksubst) |
| { |
| int r; |
| |
| if(stacksubst) |
| { |
| if(istopstackslot(&p->q1)) |
| { |
| p->q1.reg=sp; |
| p->q1.flags|=REG|DREFOBJ; |
| } |
| |
| if(istopstackslot(&p->q2)) |
| { |
| p->q2.reg=sp; |
| p->q2.flags|=REG|DREFOBJ; |
| } |
| |
| if(istopstackslot(&p->z)) |
| { |
| p->z.reg=sp; |
| p->z.flags|=REG|DREFOBJ; |
| } |
| } |
| |
| if (involvesreg(q1)) |
| q1reg = p->q1.reg; |
| else |
| q1reg = 0; |
| |
| if (involvesreg(q2)) |
| q2reg = p->q2.reg; |
| else |
| q2reg = 0; |
| |
| if (isreg(z)) { |
| zreg = p->z.reg; |
| } else { |
| if (ISFLOAT(ztyp(p))) |
| zreg = f1; |
| else |
| zreg = t1; |
| } |
| |
| return p; |
| } |
| |
| /* Determine whether the register we're about to write to will merely be passed to SetReturn. |
| If so, return 1, and convert the SetReturn IC to NOP */ |
| int next_setreturn(struct IC *p,int reg) |
| { |
| int result=0; |
| struct IC *p2=p->next; |
| while(p2 && p2->code==FREEREG) |
| p2=p2->next; |
| if(p2 && p2->code==SETRETURN && (p2->q1.flags&(REG|DREFOBJ))==REG && p2->q1.reg==reg) |
| { |
| p2->code=NOP; |
| result=1; |
| } |
| return(result); |
| } |
| |
| |
| int consecutiveaccess(struct IC *p,struct IC *p2) |
| { |
| if(!p || !p2) |
| return(0); |
| // printf("Flags %x, %x\n",p->z.flags,p2->z.flags); |
| if(((p->z.flags&(VAR|DREFOBJ))==VAR) && ((p2->z.flags&(VAR|DREFOBJ))==VAR)) |
| { |
| int result=real_offset(&p2->z)-real_offset(&p->z); |
| // printf("Got two vars\n"); |
| if(strcmp(p->z.v->identifier,p2->z.v->identifier)) |
| return(0); |
| if(isstatic(p->z.v->storage_class) && isstatic(p->z.v->storage_class)) |
| { |
| // printf("Both static - dif %d\n",result); |
| return(result); |
| } |
| if(isextern(p->z.v->storage_class) && isextern(p->z.v->storage_class)) |
| { |
| // printf("Both extern - dif %d\n",result); |
| return(result); |
| } |
| } |
| return(0); |
| } |
| |
| /* save the result (in temp) into p->z */ |
| /* Guaranteed not to touch t1/t2 unless nominated */ |
| /* or followed by a SetReturn IC. */ |
| void save_temp(FILE * f, struct IC *p, int treg) |
| { |
| int type = ztyp(p) & NQ; |
| if(DBGMSG) |
| emit(f, "\t\t\t\t\t\t// (save temp)"); |
| |
| if (isreg(z)) { |
| int target=p->z.reg; |
| if(DBGMSG) |
| emit(f, "isreg\n"); |
| if(next_setreturn(p,target)) |
| target=t1; |
| emit(f, "\tmr\t%s\n", regnames[target]); |
| } else { |
| if ((p->z.flags & DREFOBJ) && (p->z.flags & REG)) |
| treg = p->z.reg; |
| else if(isstackparam(&p->z) && !(p->z.flags & DREFOBJ)) |
| type=INT; |
| |
| if(DBGMSG) |
| emit(f, "store type %x\n",type); |
| |
| switch (type) { |
| case CHAR: |
| if (p->z.am && p->z.am->type == AM_POSTINC) |
| { |
| emit(f, "\tstbinc\t%s\n", regnames[treg]); |
| adjtempobj(f,treg,1); |
| } |
| else if ((p->z.am && p->z.am->disposable) |
| || (treg == t1)) |
| { |
| emit(f, "\tstbinc\t%s\n\t\t\t\t\t\t//Disposable, postinc doesn't matter.\n", regnames[treg]); |
| adjtempobj(f,treg,1); |
| } |
| else |
| emit(f, "\tbyt\n\tst\t%s\n", regnames[treg]); |
| break; |
| case SHORT: |
| emit(f, "\thlf\n\tst\t%s\n", regnames[treg]); |
| break; |
| case INT: |
| case LONG: |
| case POINTER: |
| // // Would need to adjust the pointer at the setup stage since we're predecrementing |
| // if (consecutiveaccess(p,p->next)==-4 || (p->z.am && p->z.am->type == AM_PREDEC)) |
| // { |
| // emit(f, "\tstdec\t%s\n", regnames[treg]); |
| // adjtempobj(f,treg,-4); |
| // } |
| if (consecutiveaccess(p,p->next)==4 || (p->z.am && p->z.am->type == AM_POSTINC)) |
| { |
| emit(f, "\tstinc\t%s\n", regnames[treg]); |
| adjtempobj(f,treg,4); |
| } |
| else |
| emit(f, "\tst\t%s\n", regnames[treg]); |
| break; |
| default: |
| printf("save_temp - type %d not yet handled\n", ztyp(p)); |
| emit(f,"\t\t\t\t\t\t// FIXME - save_temp doesn't support size\n"); |
| break; |
| } |
| } |
| if(DBGMSG) |
| emit(f, "\t\t\t\t\t\t//save_temp done\n"); |
| } |
| |
| /* save the result (in zreg) into p->z */ |
| void save_result(FILE * f, struct IC *p) |
| { |
| if(DBGMSG) |
| emit(f, "\t\t\t\t\t\t// (save result) "); |
| if (isreg(z)) { |
| if(DBGMSG) |
| emit(f, "// isreg\n"); |
| if (p->z.reg != zreg) |
| { |
| emit(f, "\tmt\t%s\n\tmr\t%s\n", regnames[zreg], regnames[p->z.reg]); |
| settempobj(f,tmp,&p->z,0,0); |
| settempobj(f,p->z.reg,&p->z,0,0); |
| } |
| } |
| else |
| { |
| emit(f, "// not reg\n"); |
| store_reg(f,zreg,&p->z,ztyp(p)); |
| } |
| return; |
| } |
| |
| #include "addressingmodes.c" |
| #include "tempregs.c" |
| #include "inlinememcpy.c" |
| #include "libcalls.c" |
| |
| /* generates the function entry code */ |
| static void function_top(FILE * f, struct Var *v, long offset) |
| { |
| int i; |
| int regcount = 0; |
| |
| cleartempobj(f,tmp); |
| cleartempobj(f,t1); |
| |
| if(DBGMSG) |
| { |
| emit(f, "\t//registers used:\n"); |
| for (i = FIRST_GPR+RESERVED_GPRS; i <= LAST_GPR; ++i) { |
| emit(f, "\t\t//%s: %s\n", regnames[i], regused[i] ? "yes" : "no"); |
| if (regused[i] && (i >= (FIRST_GPR+SCRATCH_GPRS+RESERVED_GPRS)) && (i <= LAST_GPR - 2)) |
| ++regcount; |
| } |
| } |
| |
| // Emit ctor / dtor tables |
| ctor_dtor(f, v); |
| |
| rsavesize = 0; |
| if (!special_section(f, v)) { |
| emit(f, "\t.section\t.text.%x\n", sectionid); |
| section=CODE; |
| ++sectionid; |
| } |
| if (v->storage_class == EXTERN) { |
| if ((v->flags & (INLINEFUNC | INLINEEXT)) != INLINEFUNC) { |
| if (isweak(v)) |
| emit(f, "\t.weak\t%s%s\n", idprefix, v->identifier); |
| else |
| emit(f, "\t.global\t%s%s\n", idprefix, v->identifier); |
| } |
| emit(f, "%s%s:\n", idprefix, v->identifier); |
| } else |
| emit(f, "%s%ld:\n", labprefix, zm2l(v->offset)); |
| |
| if (regcount < 3) { |
| emit(f, "\tstdec\t%s\n", regnames[sp]); |
| for (i = FIRST_GPR + SCRATCH_GPRS; i <= LAST_GPR - 3; ++i) { |
| if (regused[i] && !regscratch[i]) { |
| emit(f, "\tmt\t%s\n\tstdec\t%s\n", regnames[i], regnames[sp]); |
| rsavesize += 4; |
| } |
| } |
| } else { |
| emit(f, "\texg\t%s\n\tstmpdec\t%s\n", regnames[sp], regnames[sp]); |
| for (i = FIRST_GPR + SCRATCH_GPRS; i <= LAST_GPR - 3; ++i) { |
| if (regused[i] && !regscratch[i]) { |
| emit(f, "\tstmpdec\t%s\n", regnames[i]); |
| rsavesize += 4; |
| } |
| } |
| emit(f, "\texg\t%s\n", regnames[sp]); |
| } |
| |
| // FIXME - Allow the stack to float, in the hope that we can use stdec to adjust it. |
| |
| if ((offset == 4) && optsize) |
| emit(f, "\tstdec\tr6\t// shortest way to decrement sp by 4\n"); |
| else if (offset) { |
| emit_constanttotemp(f, -offset); |
| emit(f, "\tadd\t%s\n", regnames[sp]); |
| } |
| } |
| |
| /* generates the function exit code */ |
| /* Returns 1 if tail code was generated. */ |
| static int function_bottom(FILE * f, struct Var *v, long offset,int firsttail) |
| { |
| int i; |
| int tail=0; |
| |
| int regcount = 0; |
| for (i = FIRST_GPR + SCRATCH_GPRS + RESERVED_GPRS; i <= LAST_GPR - 3; ++i) { |
| if (regused[i] && !regscratch[i]) |
| ++regcount; |
| } |
| |
| if ((offset == 4) && optsize) |
| emit(f, "\tldinc\t%s\t// shortest way to add 4 to sp\n", regnames[sp]); |
| else if (offset) { |
| emit_constanttotemp(f, -offset); // Negative range extends one integer further than positive range. |
| emit(f, "\tsub\t%s\n", regnames[sp]); |
| } |
| |
| if(optsize) // If we're optimising for size we can potentially save some bytes in the function tails. |
| { |
| if(regcount) |
| { |
| /* We have to restore some registers. Jump into the tail code at the appropriate place. */ |
| if(regcount<(5-SCRATCH_GPRS) || !firsttail) |
| { |
| emit(f,"\t.lipcrel\t.functiontail, %d\n",((5-SCRATCH_GPRS)-regcount)*2); |
| emit(f,"\tadd\t%s\n\n",regnames[pc]); |
| } |
| if(firsttail) |
| { |
| /* This is the first time we've needed to restore registers - generate tail code */ |
| emit(f,".functiontail:\n"); |
| for (i = LAST_GPR - 3; i >= FIRST_GPR + SCRATCH_GPRS; --i) { |
| if (!regscratch[i]) |
| emit(f, "\tldinc\t%s\n\tmr\t%s\n\n", regnames[sp], regnames[i]); |
| } |
| emit(f, "\tldinc\t%s\n\tmr\t%s\n\n", regnames[sp], regnames[pc]); |
| if(f) |
| tail=1; /* Higher optimisation levels do a dummy run with null file */ |
| } |
| } |
| else |
| { |
| /* Didn't need to preserve any registers, just restore PC */ |
| emit(f, "\tldinc\t%s\n\tmr\t%s\n\n", regnames[sp], regnames[pc]); |
| } |
| } |
| else |
| { |
| for (i = LAST_GPR - 3; i >= FIRST_GPR + SCRATCH_GPRS; --i) { |
| if (regused[i] && !regscratch[i]) |
| emit(f, "\tldinc\t%s\n\tmr\t%s\n\n", regnames[sp], regnames[i]); |
| } |
| emit(f, "\tldinc\t%s\n\tmr\t%s\n\n", regnames[sp], regnames[pc]); |
| } |
| return(tail); |
| } |
| |
| /****************************************/ |
| /* End of private data and functions. */ |
| /****************************************/ |
| |
| /* Does necessary initializations for the code-generator. Gets called */ |
| /* once at the beginning and should return 0 in case of problems. */ |
| int init_cg(void) |
| { |
| int i; |
| /* Initialize some values which cannot be statically initialized */ |
| /* because they are stored in the target's arithmetic. */ |
| maxalign = l2zm(4L); |
| char_bit = l2zm(8L); |
| stackalign = l2zm(4); |
| |
| flag_832_bigendian=0; |
| if(g_flags[FLAG_BE]&USEDFLAG) |
| flag_832_bigendian=1; |
| else if(!g_flags[FLAG_BE]&USEDFLAG) |
| printf("Neither -eb nor -el specified - defaulting to little-endian\n"); |
| |
| #ifndef V09G |
| clist_copy_stack=0; |
| clist_copy_static=0; |
| clist_copy_pointer=0; |
| #endif |
| |
| // We have full load-store align, so in size mode we can pack data more tightly... |
| |
| for (i = 0; i <= MAX_TYPE; i++) { |
| sizetab[i] = l2zm(msizetab[i]); |
| align[i] = optsize ? 1 : l2zm(malign[i]); |
| |
| // Can't align everything to 4 bytes for speed without messing up struct packing. Is there a better way? |
| // align[i] = optspeed ? 4 : (optsize ? 1 : l2zm(malign[i])); |
| // align[i] = l2zm(malign[i]); |
| } |
| |
| regnames[0] = "noreg"; |
| for (i = FIRST_GPR; i <= LAST_GPR - 1; i++) { |
| regnames[i] = mymalloc(5); |
| sprintf(regnames[i], "r%d", i - FIRST_GPR); |
| regsize[i] = l2zm(4L); |
| regtype[i] = <yp; |
| regsa[i] = 0; |
| } |
| regnames[i] = mymalloc(5); |
| sprintf(regnames[i], "tmp"); |
| regsize[i] = l2zm(4L); |
| regtype[i] = <yp; |
| regsa[i] = 1; |
| for (i = FIRST_FPR; i <= LAST_FPR; i++) { |
| regnames[i] = mymalloc(10); |
| sprintf(regnames[i], "fpr%d", i - FIRST_FPR); |
| regsize[i] = l2zm(8L); |
| regtype[i] = &ldbl; |
| } |
| |
| /* Use multiple ccs. */ |
| multiple_ccs = 0; |
| |
| /* Initialize the min/max-settings. Note that the types of the */ |
| /* host system may be different from the target system and you may */ |
| /* only use the smallest maximum values ANSI guarantees if you */ |
| /* want to be portable. */ |
| /* That's the reason for the subtraction in t_min[INT]. Long could */ |
| /* be unable to represent -2147483648 on the host system. */ |
| t_min[CHAR] = l2zm(-128L); |
| t_min[SHORT] = l2zm(-32768L); |
| t_min[INT] = zmsub(l2zm(-2147483647L), l2zm(1L)); |
| t_min[LONG] = t_min(INT); |
| t_min[LLONG] = zmlshift(l2zm(1L), l2zm(63L)); |
| t_min[MAXINT] = t_min(LLONG); |
| t_max[CHAR] = ul2zum(127L); |
| t_max[SHORT] = ul2zum(32767UL); |
| t_max[INT] = ul2zum(2147483647UL); |
| t_max[LONG] = t_max(INT); |
| t_max[LLONG] = zumrshift(zumkompl(ul2zum(0UL)), ul2zum(1UL)); |
| t_max[MAXINT] = t_max(LLONG); |
| tu_max[CHAR] = ul2zum(255UL); |
| tu_max[SHORT] = ul2zum(65535UL); |
| tu_max[INT] = ul2zum(4294967295UL); |
| tu_max[LONG] = t_max(UNSIGNED | INT); |
| tu_max[LLONG] = zumkompl(ul2zum(0UL)); |
| tu_max[MAXINT] = t_max(UNSIGNED | LLONG); |
| |
| /* Reserve a few registers for use by the code-generator. */ |
| /* This is not optimal but simple. */ |
| tmp = FIRST_GPR + 8; |
| pc = FIRST_GPR + 7; |
| sp = FIRST_GPR + 6; |
| t1 = FIRST_GPR; // r0, also return register. |
| t2 = FIRST_GPR + 1; |
| // f1=FIRST_FPR; |
| // f2=FIRST_FPR+1; |
| |
| for (i = FIRST_GPR; i <= LAST_GPR; i++) |
| regscratch[i] = 0; |
| for (i = FIRST_FPR; i <= LAST_FPR; i++) |
| regscratch[i] = 0; |
| |
| regsa[FIRST_GPR] = 1; // Allocate the return register |
| regsa[t1] = 1; |
| regsa[t2] = 0; |
| regsa[sp] = 1; |
| regsa[pc] = 1; |
| regsa[tmp] = 1; |
| regscratch[FIRST_GPR] = 0; |
| for(i=FIRST_GPR+RESERVED_GPRS;i<(FIRST_GPR+RESERVED_GPRS+SCRATCH_GPRS);++i) |
| regscratch[i] = 1; |
| regscratch[sp] = 0; |
| regscratch[pc] = 0; |
| |
| target_macros = marray; |
| |
| return 1; |
| } |
| |
| void init_db(FILE * f) |
| { |
| } |
| |
| int freturn(struct Typ *t) |
| /* Returns the register in which variables of type t are returned. */ |
| /* If the value cannot be returned in a register returns 0. */ |
| /* A pointer MUST be returned in a register. The code-generator */ |
| /* has to simulate a pseudo register if necessary. */ |
| { |
| if (ISFLOAT(t->flags)) |
| return 0; |
| if (ISSTRUCT(t->flags) || ISUNION(t->flags)) |
| return 0; |
| if (zmleq(szof(t), l2zm(4L))) |
| return FIRST_GPR; |
| else |
| return 0; |
| } |
| |
| int reg_pair(int r, struct rpair *p) |
| /* Returns 0 if the register is no register pair. If r */ |
| /* is a register pair non-zero will be returned and the */ |
| /* structure pointed to p will be filled with the two */ |
| /* elements. */ |
| { |
| return 0; |
| } |
| |
| /* estimate the cost-saving if object o from IC p is placed in |
| register r */ |
| int cost_savings(struct IC *p, int r, struct obj *o) |
| { |
| int c = p->code; |
| if(o->v && isextern(o->v->storage_class)) // Externs are particularly costly due to the ldinc r7 shuffle |
| return(o->flags & DREFOBJ ? 5 : 3); |
| if (o->flags & VKONST) { |
| if (isextern(o->flags) || isstatic(o->flags)) |
| return 2; |
| else { |
| struct obj *o2 = &o->v->cobj; |
| int c = count_constantchunks(o2->val.vmax); |
| return c - 1; |
| } |
| } |
| if (o->flags & DREFOBJ) |
| return 2; |
| if (c == SETRETURN)// && r == p->z.reg && !(o->flags & DREFOBJ)) |
| return 1; |
| if (c == GETRETURN)// && r == p->q1.reg && !(o->flags & DREFOBJ)) |
| return 1; |
| return 1; |
| } |
| |
| int regok(int r, int t, int mode) |
| /* Returns 0 if register r cannot store variables of */ |
| /* type t. If t==POINTER and mode!=0 then it returns */ |
| /* non-zero only if the register can store a pointer */ |
| /* and dereference a pointer to mode. */ |
| { |
| if (r == 0) |
| return 0; |
| t &= NQ; |
| if (ISFLOAT(t) && r >= FIRST_FPR && r <= LAST_FPR) |
| return 1; |
| if (t == POINTER && r >= FIRST_GPR && r <= LAST_GPR) |
| return 1; |
| if (t >= CHAR && t <= LONG && r >= FIRST_GPR && r <= LAST_GPR) |
| return 1; |
| return 0; |
| } |
| |
| int dangerous_IC(struct IC *p) |
| /* Returns zero if the IC p can be safely executed */ |
| /* without danger of exceptions or similar things. */ |
| /* vbcc may generate code in which non-dangerous ICs */ |
| /* are sometimes executed although control-flow may */ |
| /* never reach them (mainly when moving computations */ |
| /* out of loops). */ |
| /* Typical ICs that generate exceptions on some */ |
| /* machines are: */ |
| /* - accesses via pointers */ |
| /* - division/modulo */ |
| /* - overflow on signed integer/floats */ |
| { |
| int c = p->code; |
| if ((p->q1.flags & DREFOBJ) || (p->q2.flags & DREFOBJ) |
| || (p->z.flags & DREFOBJ)) |
| return 1; |
| if ((c == DIV || c == MOD) && !isconst(q2)) |
| return 1; |
| return 0; |
| } |
| |
| int must_convert(int o, int t, int const_expr) |
| /* Returns zero if code for converting np to type t */ |
| /* can be omitted. */ |
| /* On the PowerPC cpu pointers and 32bit */ |
| /* integers have the same representation and can use */ |
| /* the same registers. */ |
| { |
| int op = o & NQ, tp = t & NQ; |
| if ((op == INT || op == LONG || op == POINTER) |
| && (tp == INT || tp == LONG || tp == POINTER)) |
| return 0; |
| if (op == DOUBLE && tp == LDOUBLE) |
| return 0; |
| if (op == LDOUBLE && tp == DOUBLE) |
| return 0; |
| return 1; |
| } |
| |
| void gen_ds(FILE * f, zmax size, struct Typ *t) |
| /* This function has to create <size> bytes of storage */ |
| /* initialized with zero. */ |
| { |
| if (newobj && section != SPECIAL) |
| emit(f, "%ld\n", zm2l(size)); |
| else |
| emit(f, "\t.space\t%ld\n", zm2l(size)); |
| newobj = 0; |
| } |
| |
| |
| /* This function has to make sure the next data is |
| aligned to multiples of <align> bytes. |
| If the speed optimisation flag is set, always align |
| to four bytes. */ |
| void gen_align(FILE * f, zmax align) |
| { |
| if(optspeed) |
| emit(f,"\t.align\t4\n"); |
| else if (zm2l(align) > 1) |
| emit(f, "\t.align\t%d\n", align); |
| } |
| |
| void gen_var_head(FILE * f, struct Var *v) |
| /* This function has to create the head of a variable */ |
| /* definition, i.e. the label and information for */ |
| /* linkage etc. */ |
| { |
| int constflag; |
| char *sec; |
| if (v->clist) |
| constflag = is_const(v->vtyp); |
| if (v->storage_class == STATIC) { |
| if (ISFUNC(v->vtyp->flags)) |
| return; |
| if (!special_section(f, v)) { |
| if (v->clist && (!constflag)) { // || (g_flags[2] & USEDFLAG)) |
| // && section != DATA) { |
| emit(f, "%s.%x\n",dataname,sectionid); |
| ++sectionid; |
| if (f) |
| section = DATA; |
| } |
| if (v->clist && constflag) { // && !(g_flags[2] & USEDFLAG) |
| // && section != RODATA) { |
| emit(f, "%s.%x\n",rodataname,sectionid); |
| ++sectionid; |
| if (f) |
| section = RODATA; |
| } |
| if (!v->clist) { // && section != BSS) { |
| emit(f, "%s.%x\n",bssname,sectionid); |
| ++sectionid; |
| if (f) |
| section = BSS; |
| } |
| } |
| if (v->clist || section == SPECIAL) { |
| gen_align(f, falign(v->vtyp)); |
| emit(f, "%s%ld:\n", labprefix, zm2l(v->offset)); |
| } else { |
| gen_align(f, falign(v->vtyp)); |
| emit(f, "\t.lcomm\t%s%ld,", labprefix, zm2l(v->offset)); |
| } |
| newobj = 1; |
| } |
| if (v->storage_class == EXTERN) { |
| // emit(f, "\t.global\t%s%s\n", idprefix, v->identifier); |
| if (v->flags & (DEFINED | TENTATIVE)) { |
| if (!special_section(f, v)) { |
| if (v->clist && (!constflag)) { // || (g_flags[2] & USEDFLAG)) |
| // && section != DATA) { |
| emit(f, "%s.%x\n",dataname,sectionid); |
| ++sectionid; |
| if (f) |
| section = DATA; |
| } |
| if (v->clist && constflag) { // && !(g_flags[2] & USEDFLAG) |
| // && section != RODATA) { |
| emit(f, "%s.%x\n",rodataname,sectionid); |
| ++sectionid; |
| if (f) |
| section = RODATA; |
| } |
| if (!v->clist) { // && section != BSS) { |
| emit(f, "%s.%x\n",bssname,sectionid); |
| ++sectionid; |
| if (f) |
| section = BSS; |
| } |
| } |
| if (v->clist || section == SPECIAL) { |
| gen_align(f, falign(v->vtyp)); |
| if (isweak(v)) |
| emit(f, "\t.weak\t%s%s\n", idprefix, v->identifier); |
| else |
| emit(f, "\t.global\t%s%s\n", idprefix, v->identifier); |
| emit(f, "%s%s:\n", idprefix, v->identifier); |
| } else { |
| gen_align(f, falign(v->vtyp)); |
| if (isweak(v)) |
| emit(f, "\t.weak\t%s%s\n", idprefix, v->identifier); |
| else { |
| emit(f, "\t.global\t%s%s\n", idprefix, v->identifier); |
| emit(f, "\t.comm\t%s%s,", idprefix, v->identifier); |
| } |
| } |
| newobj = 1; |
| } |
| } |
| } |
| |
| void gen_dc(FILE * f, int t, struct const_list *p) |
| /* This function has to create static storage */ |
| /* initialized with const-list p. */ |
| { |
| if (!p->tree) { |
| switch (t & NQ) { |
| case CHAR: |
| emit(f, "\t.byte\t"); |
| break; |
| case SHORT: |
| emit(f, "\t.short\t"); |
| break; |
| case LONG: |
| case INT: |
| case MAXINT: |
| case POINTER: |
| emit(f, "\t.int\t"); |
| break; |
| case LLONG: |
| emit(f, "//FIXME - unsupported type\n"); |
| emit(f, "\t.long\t"); |
| // ierror(0); |
| break; |
| default: |
| printf("gen_dc: unsupported type 0x%x\n", t); |
| ierror(0); |
| } |
| emitval(f, &p->val, t & NU); |
| emit(f, "\n"); |
| |
| #if 0 |
| if (ISFLOAT(t)) { |
| /* auch wieder nicht sehr schoen und IEEE noetig */ |
| unsigned char *ip; |
| ip = (unsigned char *)&p->val.vdouble; |
| emit(f, "0x%02x%02x%02x%02x", ip[0], ip[1], ip[2], ip[3]); |
| if ((t & NQ) != FLOAT) { |
| emit(f, ",0x%02x%02x%02x%02x", ip[4], ip[5], ip[6], ip[7]); |
| } |
| } else { |
| emitval(f, &p->val, t & NU); |
| } |
| #endif |
| } else { |
| struct obj *o = &p->tree->o; |
| emit(f, "\t\t\t\t\t\t// Declaring from tree\n"); |
| if (isextern(o->v->storage_class)) { |
| emit(f, "\t\t\t\t\t\t// extern (offset %d)\n", o->val.vmax); |
| if (o->val.vmax) |
| emit(f, "\t.ref\t_%s, %d\n", o->v->identifier, o->val.vmax); |
| else |
| emit(f, "\t.ref\t_%s\n", o->v->identifier); |
| } else if (isstatic(o->v->storage_class)) { |
| emit(f, "\t\t\t\t\t\t// static\n"); |
| if(o->val.vlong) |
| emit(f, "\t.ref\t%s%d,%d\n", labprefix, zm2l(o->v->offset),o->val.vlong); |
| else |
| emit(f, "\t.ref\t%s%d\n", labprefix, zm2l(o->v->offset)); |
| } else { |
| printf("error: GenDC (tree) - unknown storage class 0x%x!\n", o->v->storage_class); |
| } |
| } |
| newobj = 0; |
| } |
| |
| |
| /* Return 1 if any of p's operands uses predec or postinc addressing mode */ |
| int check_am(struct IC *p) |
| { |
| if(p->q1.am && (p->q1.am->type==AM_POSTINC || p->q1.am->type==AM_PREDEC)) |
| return(1); |
| if(p->q2.am && (p->q2.am->type==AM_POSTINC || p->q2.am->type==AM_PREDEC)) |
| return(1); |
| if(p->z.am && (p->z.am->type==AM_POSTINC || p->z.am->type==AM_PREDEC)) |
| return(1); |
| return(0); |
| } |
| |
| /* The main code-generation routine. */ |
| /* f is the stream the code should be written to. */ |
| /* p is a pointer to a doubly linked list of ICs */ |
| /* containing the function body to generate code for. */ |
| /* v is a pointer to the function. */ |
| /* offset is the size of the stackframe the function */ |
| /* needs for local variables. */ |
| |
| void gen_code(FILE * f, struct IC *p, struct Var *v, zmax offset) |
| /* The main code-generation. */ |
| { |
| static int idemp = 0; |
| static int firsttail=1; |
| int reversecmp=0; |
| int c, t, i; |
| struct IC *m; |
| argsize = 0; |
| // if(DEBUG&1) |
| |
| if(!p) |
| printf("(gen_code called with null IC list?)\n"); |
| |
| for (c = 1; c <= MAXR; c++) |
| regs[c] = regsa[c]; |
| pushed = 0; |
| notyetpopped = 0; |
| |
| #if 0 |
| if (!idemp) { |
| sectionid = 0; |
| if (p && p->file) { |
| int v; |
| char *c = p->file; |
| idemp = 1; |
| while (v = *c++) { |
| sectionid <<= 3; |
| sectionid ^= v; |
| } |
| printf("Created section ID %x\n",sectionid); |
| } |
| else |
| printf("No sectionid created (%x, %x)\n",p,p ? p->file : 0); |
| } |
| #endif |
| |
| for (m = p; m; m = m->next) { |
| c = m->code; |
| t = m->typf & NU; |
| if (c == ALLOCREG) { |
| regs[m->q1.reg] = 1; |
| continue; |
| } |
| if (c == FREEREG) { |
| regs[m->q1.reg] = 0; |
| continue; |
| } |
| |
| /* convert MULT/DIV/MOD with powers of two */ |
| // Perversely, mul is faster than shifting on 832, so we only want to do this for div. |
| // FIXME - we can do this for signed values too. |
| if ((t & NQ) <= LONG && (m->q2.flags & (KONST | DREFOBJ)) == KONST && (t & NQ) <= LONG |
| && (((c == DIV || c == MOD) && (t & UNSIGNED)))) { |
| eval_const(&m->q2.val, t); |
| i = pof2(vmax); |
| if (i) { |
| if (c == MOD) { |
| vmax = zmsub(vmax, l2zm(1L)); |
| m->code = AND; |
| } else { |
| vmax = l2zm(i - 1); |
| if (c == DIV) |
| m->code = RSHIFT; |
| else |
| m->code = LSHIFT; |
| } |
| c = m->code; |
| gval.vmax = vmax; |
| eval_const(&gval, MAXINT); |
| if (c == AND) { // FIXME - why? |
| insert_const(&m->q2.val, t); |
| } else { |
| insert_const(&m->q2.val, INT); |
| p->typf2 = INT; |
| } |
| } |
| } |
| } |
| |
| for (c = 1; c <= MAXR; c++) { |
| if (regsa[c] || regused[c]) { |
| BSET(regs_modified, c); |
| } |
| } |
| localsize = (zm2l(offset) + 3) / 4 * 4; |
| |
| // printf("\nSeeking addressing modes for function %s\n",v->identifier); |
| find_addressingmodes(p); |
| |
| function_top(f, v, localsize); |
| // printf("%s:\n",v->identifier); |
| |
| for (; p; p = p->next) { |
| // printic(stdout,p); |
| c = p->code; |
| t = q1typ(p); |
| |
| if (c == NOP) { |
| p->z.flags = 0; |
| continue; |
| } |
| if (c == ALLOCREG) { |
| if(DBGMSG) |
| emit(f, "\t\t\t\t\t\t// allocreg %s\n", regnames[p->q1.reg]); |
| regs[p->q1.reg] = 1; |
| continue; |
| } |
| if (c == FREEREG) { |
| if(DBGMSG) |
| emit(f, "\t\t\t\t\t\t// freereg %s\n", regnames[p->q1.reg]); |
| regs[p->q1.reg] = 0; |
| continue; |
| } |
| if (c == LABEL) { |
| int i; |
| emit(f, "%s%d: # \n", labprefix, t); |
| cleartempobj(f,tmp); // Can't carry temporary context past a label |
| cleartempobj(f,t1); |
| continue; |
| } |
| |
| if (DBGMSG && p->file) |
| emit(f, "\n\t\t\t\t\t\t//%s, line %d\n", p->file, p->line); |
| if(p->q1.am && p->q1.am->disposable) |
| emit(f, "\t\t\t\t\t\t// Q1 disposable\n"); |
| if(p->q2.am && p->q2.am->disposable) |
| emit(f, "\t\t\t\t\t\t// Q2 disposable\n"); |
| if(p->z.am && p->z.am->disposable) |
| emit(f, "\t\t\t\t\t\t// Z disposable\n"); |
| |
| // OK |
| if (c == BRA) { |
| if(0) // FIXME - could duplicate function tail here. Perhaps do it depending on number of saved registers? |
| function_bottom(f, v, localsize, 0); |
| else |
| emit_pcreltotemp(f, labprefix, t); |
| emit(f, "\tadd\t%s\n", regnames[pc]); |
| continue; |
| } |
| // OK |
| if (c >= BEQ && c < BRA) { |
| if(reversecmp) |
| { |
| switch(c) |
| { |
| case BLT: |
| c=BGT; |
| break; |
| case BLE: |
| c=BGE; |
| break; |
| case BGT: |
| c=BLT; |
| break; |
| case BGE: |
| c=BLE; |
| break; |
| } |
| } |
| emit(f, "\tcond\t%s\n",ccs[c - BEQ]); |
| if(DBGMSG) |
| emit(f, "\t\t\t\t\t\t//conditional branch %s\n",reversecmp ? "reversed" : "regular"); |
| reversecmp=0; |
| emit_pcreltotemp(f, labprefix, t); // FIXME - double-check that we shouldn't include an offset here. |
| emit(f, "\t\tadd\tr7\n"); |
| continue; |
| } |
| // Investigate - but not currently seeing it used. |
| if (c == MOVETOREG) { |
| emit(f, "\t\t\t\t\t\t//CHECKME movetoreg\n"); |
| emit_objtoreg(f, &p->q1, ztyp(p),zreg); |
| continue; |
| } |
| // Investigate - but not currently seeing it used. |
| if (c == MOVEFROMREG) { |
| emit(f, "\t\t\t\t\t\t//CHECKME movefromreg\n"); |
| store_reg(f, p->q1.reg, &p->z, regtype[p->q1.reg]->flags); |
| continue; |
| } |
| // Reject types we can't handle - anything beyond a pointer and chars with more than 1 byte. |
| // if ((c == PUSH) |
| // && ((t & NQ) > POINTER || ((t & NQ) == CHAR && zm2l(p->q2.val.vmax) != 1))) { |
| // printf("Pushing a type we don't yet handle: 0x%x\n", t); |
| // ierror(0); |
| // } |
| |
| if ((c == ASSIGN) && ((t & NQ) > UNION)) { |
| printf("Assignment of a type we don't yet handle: 0x%x\n", t); |
| ierror(0); |
| } |
| |
| // Avoid stack top slot trickery if the operation involves pushing operands to the stack |
| if(c==DIV || c==MOD || |
| ((c==ASSIGN || c==PUSH) && ((t & NQ) > POINTER || ((t & NQ) == CHAR && zm2l(p->q2.val.vmax) != 1)))) |
| p = preload(f, p, 0); // Setup zreg, etc. |
| else |
| p = preload(f, p, 1); // Setup zreg, etc. |
| |
| c = p->code; |
| |
| if (c == SUBPFP) |
| c = SUB; |
| if (c == ADDI2P) |
| c = ADD; |
| if (c == SUBIFP) |
| c = SUB; |
| |
| // emit(f, "// code 0x%x, q1->v: %x\n", c,&p->q1.v); |
| // if(p->prev && matchobj(f,&p->q1,&p->prev->q1)) |
| // emit(f, "// Matching objs found\n", p->prev->code,&p->prev->q1.v); |
| |
| if (c == CONVERT) { |
| if(DBGMSG) |
| emit(f, "\t\t\t\t\t\t//FIXME convert\n"); |
| if (ISFLOAT(q1typ(p)) || ISFLOAT(ztyp(p))) { |
| printf("Float not yet supported\n"); |
| ierror(0); |
| } |
| if (sizetab[q1typ(p) & NQ] < sizetab[ztyp(p) & NQ]) { |
| int shamt = 0; |
| if(DBGMSG) |
| emit(f,"\t\t\t\t\t\t//Converting to wider type...\n"); |
| switch (q1typ(p) & NU) { |
| case CHAR | UNSIGNED: |
| case SHORT | UNSIGNED: |
| if(DBGMSG) |
| emit(f,"\t\t\t\t\t\t//But unsigned, so no need to extend\n"); |
| |
| if(involvesreg(z)) { |
| emit_prepobj(f, &p->z, ztyp(p), zreg, 0); |
| emit_objtoreg(f, &p->q1, q1typ(p), tmp); |
| save_temp(f, p, zreg); |
| // WARNING - might need to invalidate temp objects here... |
| } else { |
| emit_objtoreg(f, &p->q1, q1typ(p), zreg); |
| save_result(f, p); |
| // WARNING - might need to invalidate temp objects here... |
| } |
| break; |
| case CHAR: |
| emit_objtoreg(f, &p->q1, q1typ(p), zreg); |
| emit_constanttotemp(f,0xffffff80); |
| emit(f,"\tadd\t%s\n",regnames[zreg]); |
| emit(f,"\txor\t%s\n",regnames[zreg]); |
| cleartempobj(f,zreg); |
| save_result(f, p); |
| break; |
| case SHORT: |
| emit_objtoreg(f, &p->q1, q1typ(p), zreg); |
| emit_constanttotemp(f,0xffff8000); |
| emit(f,"\tadd\t%s\n",regnames[zreg]); |
| emit(f,"\txor\t%s\n",regnames[zreg]); |
| cleartempobj(f,zreg); |
| save_result(f, p); |
| break; |
| } |
| // settempobj(f,zreg,&p->z,0,0); |
| } else if(sizetab[q1typ(p) & NQ] >= sizetab[ztyp(p) & NQ]) { // Reducing the size, must mask off excess bits... |
| if(DBGMSG) |
| emit(f,"\t\t\t\t\t\t// (convert - reducing type %x to %x\n",q1typ(p),ztyp(p)); |
| |
| // If Z is not a register then we're storing a halfword or byte, and thus don't need to mask... |
| |
| if(((p->q1.flags&(REG|DREFOBJ))==REG) && (p->z.flags&(REG|DREFOBJ))!=REG) { |
| if(p->z.flags&DREFOBJ) { // Can't use stmpdec for dereferenced objects |
| emit_prepobj(f, &p->z, t, zreg, 0); // Need an offset |
| emit_objtoreg(f, &p->q1, q1typ(p), tmp); |
| save_temp(f,p,zreg); |
| #if 0 |
| emit_prepobj(f, &p->z, t, tmp, 0); // Need an offset |
| emit(f, "\texg\t%s\n", regnames[q1reg]); |
| // if(!isstackparam(&p->z) || (p->z.flags&DREFOBJ)) |
| emit_sizemod(f,ztyp(p)); |
| emit(f, "\tst\t%s\n", regnames[q1reg]); |
| if(p->z.am && p->z.am->disposable && p->q1.am && p->q1.am->disposable) |
| emit(f, "\t\t\t\t\t\t// Both q1 and z are disposable, not bothering to undo exg\n"); |
| else |
| emit(f, "\texg\t%s\n", regnames[q1reg]); |
| #endif |
| } |
| else { |
| // Use stmpdec if q1 is already in a register... |
| emit_prepobj(f, &p->z, ztyp(p), tmp, 4); // Need an offset |
| if(!isstackparam(&p->z)) |
| emit_sizemod(f,ztyp(p)); |
| emit(f,"\tstmpdec\t%s\n",regnames[q1reg]); |
| } |
| } |
| else { // Destination is a register - we must mask... |
| // Potential optimisation here - track which ops could have caused a value to require truncation. |
| // Also figure out what's happening next to the value. If it's only being added, anded, ored, xored |
| // and then truncated by a write to memory we don't need to worry. |
| if(!isreg(q1) || !isreg(z) || q1reg!=zreg) // Do we just need to mask in place, or move the value first? |
| { |
| if(!isreg(z)) |
| zreg=t1; |
| emit_prepobj(f, &p->z, ztyp(p), t1, 0); |
| |
| emit_objtoreg(f, &p->q1, t,tmp); |
| emit(f,"\t\t\t\t\t\t//Saving to reg %s\n",regnames[zreg]); |
| save_temp(f, p, zreg); |
| } |
| // else |
| if(zreg!=sp && (p->z.flags&(DREFOBJ|REG))==REG) |
| { |
| switch(ztyp(p)&NQ) { |
| case SHORT: |
| emit_constanttotemp(f, 0xffff); |
| emit(f, "\tand\t%s\n", regnames[zreg]); |
| break; |
| case CHAR: |
| emit_constanttotemp(f, 0xff); |
| emit(f, "\tand\t%s\n", regnames[zreg]); |
| break; |
| default: |
| emit(f,"\t\t\t\t\t\t//No need to mask - same size\n"); |
| break; |
| } |
| } |
| } |
| } |
| continue; |
| } |
| |
| if (c == KOMPLEMENT) { |
| if(DBGMSG) |
| emit(f, "\t\t\t\t\t\t//comp\n"); |
| emit_objtoreg(f, &p->q1, q1typ(p), zreg); |
| emit_constanttotemp(f,-1); |
| emit(f, "\txor\t%s\n", regnames[zreg]); |
| // cleartempobj(f,zreg); |
| save_result(f, p); |
| continue; |
| } |
| // May not need to actually load the register here - certainly check before emitting code. |
| if (c == SETRETURN) { |
| if(DBGMSG) |
| emit(f, "\t\t\t\t\t\t//setreturn\n"); |
| emit_objtoreg(f, &p->q1, q1typ(p), zreg); |
| BSET(regs_modified, p->z.reg); |
| continue; |
| } |
| // Investigate - May not be needed for register mode? |
| if (c == GETRETURN) { |
| if(DBGMSG) |
| emit(f, "\t\t\t\t\t\t// (getreturn)"); |
| if (p->q1.reg) { |
| zreg = p->q1.reg; |
| save_result(f, p); |
| } else { |
| if(DBGMSG) |
| emit(f, " not reg\n"); |
| p->z.flags = 0; |
| } |
| continue; |
| } |
| // OK - figure out what the bvunite stuff is all about. |
| if (c == CALL) { |
| int reg; |
| if(DBGMSG) |
| emit(f, "\t\t\t\t\t\t//call\n"); |
| if ((p->q1.flags & (VAR | DREFOBJ)) == VAR && p->q1.v->fi && p->q1.v->fi->inline_asm) { |
| emit_inline_asm(f, p->q1.v->fi->inline_asm); |
| cleartempobj(f,t1); |
| cleartempobj(f,tmp); |
| /* FIXME - restore stack from pushed arguments? */ |
| } else { |
| /* FIXME - deal with different object types here */ |
| if (p->q1.v->storage_class == STATIC) { |
| // FIXME - double-check that we shouldn't include an offset here. |
| emit_pcreltotemp2(f, &p->q1); |
| if (p->q1.flags & DREFOBJ) { |
| emit(f, "\taddt\t%s\t//Deref function pointer\n", regnames[pc]); |
| emit(f, "\tldt\n\texg\t%s\n", regnames[pc]); |
| } else |
| emit(f, "\tadd\t%s\n", regnames[pc]); |
| } else if (p->q1.v->storage_class == EXTERN) { |
| if (p->q1.flags & DREFOBJ) { // Is this a function pointer? |
| emit_externtotemp(f, p->q1.v->identifier, p->q1.val.vmax); |
| emit(f, "\tldt\t// deref function ptr\n"); |
| emit(f, "\texg\t%s\n", regnames[pc]); |
| } |
| else { |
| emit_pcreltotemp2(f, &p->q1); |
| emit(f, "\tadd\t%s\n", regnames[pc]); |
| } |
| } else { |
| emit_objtoreg(f, &p->q1, t, tmp); |
| emit(f, "\texg\t%s\n", regnames[pc]); |
| } |
| |
| cleartempobj(f,tmp); |
| |
| /* If we have an addressingmode, see if we're able to defer stack popping. */ |
| if(p->z.am) |
| { |
| switch(p->z.am->deferredpop) |
| { |
| /* If we couldn't defer popping due to flow control changes, we need to pop any previously |
| deferred stack entries at this point.*/ |
| case DEFERREDPOP_FLOWCONTROL: |
| emit(f,"\t\t\t\t\t\t// Flow control - popping %d + %d bytes\n",pushedargsize(p),notyetpopped); |
| if(pushedargsize(p)+notyetpopped) |
| { |
| emit_constanttotemp(f, pushedargsize(p)+notyetpopped); |
| emit(f, "\tadd\t%s\n", regnames[sp]); |
| } |
| pushed -= pushedargsize(p); |
| notyetpopped=0; |
| break; |
| |
| /* If we couldn't defer popping due to nested calls then we only pop this function's stack entries. */ |
| case DEFERREDPOP_NESTEDCALLS: |
| emit(f,"\t\t\t\t\t\t// Nested call - popping %d bytes\n",pushedargsize(p)); |
| if(pushedargsize(p)) |
| { |
| emit_constanttotemp(f, pushedargsize(p)); |
| emit(f, "\tadd\t%s\n", regnames[sp]); |
| } |
| pushed -= pushedargsize(p); |
| break; |
| |
| /* Otherwise, we're OK to defer popping until later. */ |
| case DEFERREDPOP_OK: |
| notyetpopped+=pushedargsize(p); |
| pushed -= pushedargsize(p); |
| emit(f,"\t\t\t\t\t\t// Deferred popping of %d bytes (%d in total)\n",pushedargsize(p),notyetpopped); |
| break; |
| } |
| } |
| else if(pushedargsize(p)) |
| { |
| emit_constanttotemp(f, pushedargsize(p)); |
| pushed -= pushedargsize(p); |
| emit(f, "\tadd\t%s\n", regnames[sp]); |
| } |
| // cleartempobj(f,tmp); |
| cleartempobj(f,t1); |
| } |
| /*FIXME*/ |
| if ((p->q1.flags & (VAR | DREFOBJ)) == VAR && p->q1.v->fi |
| && (p->q1.v->fi->flags & ALL_REGS)) { |
| bvunite(regs_modified, p->q1.v->fi->regs_modified, RSIZE); |
| } else { |
| int i; |
| for (i = 1; i <= MAXR; i++) { |
| if (regscratch[i]) |
| BSET(regs_modified, i); |
| } |
| } |
| continue; |
| } |
| |
| if ((c == ASSIGN || c == PUSH) && t == 0) { |
| printf("Bad type for assign / push\n"); |
| ierror(0); |
| } |
| // Basically OK. |
| if (c == PUSH) { |
| int matchreg; |
| if(DBGMSG) |
| emit(f, "\t\t\t\t\t\t// (a/p push)\n"); |
| |
| /* Handle composite types */ |
| if((t & NQ) > POINTER || ((t & NQ) == CHAR && zm2l(p->q2.val.vmax) != 1)) { |
| // if(DBGMSG) |
| emit(f,"\t\t\t\t\t\t// Pushing composite type - size %d, pushed size %d\n",opsize(p),pushsize(p)); |
| emit_inlinepush(f,p,t); |
| pushed += pushsize(p); |
| } |
| else |
| { |
| /* need to take dt into account */ |
| if(DBGMSG) |
| emit(f, "\t\t\t\t\t\t// a: pushed %ld, regnames[sp] %s\n", pushed, regnames[sp]); |
| switch(t&NQ) |
| { |
| case INT: |
| case LONG: |
| case POINTER: |
| emit_objtoreg(f, &p->q1, t, tmp); |
| emit(f, "\tstdec\t%s\n", regnames[sp]); |
| break; |
| default: |
| printf("Pushing unhandled type 0x%x to the stack\n",t); |
| ierror(0); |
| break; |
| } |
| pushed += pushsize(p); |
| } |
| continue; |
| } |
| |
| if (c == ASSIGN) { |
| if(DBGMSG) |
| emit(f, "\t\t\t\t\t\t// (a/p assign)\n"); |
| if (((t & NQ) == STRUCT) || ((t & NQ) == UNION) || ((t & NQ) == ARRAY) |
| || ((t & NQ) == CHAR && opsize(p) != 1)) { |
| emit_inlinememcpy(f,p,t); |
| } else { |
| // Is the small speedup here worth the complexity? (Yes, because it improves code density) |
| // Use stmpdec if q1 is already in a register and we're not using addressing modes... |
| if(!check_am(p) && ((p->q1.flags&(REG|DREFOBJ))==REG) && !(p->z.flags®)) |
| { |
| if(p->z.flags&DREFOBJ) // Can't use stmpdec for dereferenced objects |
| { |
| emit_prepobj(f, &p->z, t, tmp, 0); |
| emit(f, "\texg\t%s\n", regnames[q1reg]); |
| emit_sizemod(f,t); |
| emit(f, "\tst\t%s\n", regnames[q1reg]); |
| if(p->z.am && p->z.am->disposable) |
| { |
| cleartempobj(f,tmp); |
| emit(f, "\t\t\t\t\t\t// Object is disposable, not bothering to undo exg\n"); |
| } |
| else |
| emit(f, "\texg\t%s\n", regnames[q1reg]); |
| } |
| else |
| { |
| emit_prepobj(f, &p->z, t, tmp, 4); // Need an offset |
| if(!isstackparam(&p->z)) |
| emit_sizemod(f,t); |
| emit(f,"\tstmpdec\t%s\n",regnames[q1reg]); |
| cleartempobj(f,tmp); |
| } |
| } |
| else |
| { |
| emit_prepobj(f, &p->z, t, t1, 0); |
| emit_objtoreg(f, &p->q1, t, tmp); |
| save_temp(f, p, t1); |
| } |
| } |
| continue; |
| } |
| // Seems to work. |
| if (c == ADDRESS) { |
| if(DBGMSG) |
| emit(f, "\t\t\t\t\t\t// (address)\n"); |
| if(involvesreg(z)) |
| { |
| emit_prepobj(f, &p->q1, POINTER, tmp, 0); |
| save_temp(f,p,zreg); |
| } |
| else |
| { |
| emit_prepobj(f, &p->q1, POINTER, zreg, 0); |
| save_result(f, p); |
| } |
| continue; |
| } |
| // OK |
| if (c == MINUS) { |
| if(DBGMSG) |
| emit(f, "\t\t\t\t\t\t// (minus)\n"); |
| emit_objtoreg(f, &p->q1, q1typ(p), zreg); |
| emit_constanttotemp(f,0); |
| emit(f, "\texg %s\n\tsub %s\n", regnames[zreg], regnames[zreg]); |
| settempobj(f,tmp,&p->q1,0,0); // Temp contains un-negated value |
| // cleartempobj(f,tmp); |
| save_result(f, p); |
| continue; |
| } |
| // Compare - # |
| // Revisit |
| if (c == TEST) { |
| if(DBGMSG) |
| emit(f, "\t\t\t\t\t\t// (test)\n"); |
| if(!emit_objtoreg(f, &p->q1, t, tmp)) /* emit_objtoreg might already have set the Z flag */ |
| { |
| emit(f,"\t\t\t\t// flags %x\n",p->q1.flags); |
| if ((p->q1.flags & (REG|DREFOBJ)) == REG) // Can avoid mr if the value came from a register |
| emit(f, "\tand\t%s\n", regnames[p->q1.reg]); |
| else |
| { |
| emit(f, "\tmr\t%s\n\tand\t%s\n", regnames[t1], regnames[t1]); |
| settempobj(f,t1,&p->q1,0,0); |
| } |
| // cleartempobj(f,tmp); |
| // cleartempobj(f,t1); |
| } |
| continue; |
| } |
| // Compare |
| // Revisit |
| if (c == COMPARE) { |
| if(DBGMSG) |
| { |
| emit(f, "\t\t\t\t\t\t// (compare)"); |
| if (q1typ(p) & UNSIGNED) |
| emit(f, " (q1 unsigned)"); |
| else |
| emit(f, " (q1 signed)"); |
| if (q2typ(p) & UNSIGNED) |
| emit(f, " (q2 unsigned)"); |
| else |
| emit(f, " (q2 signed)"); |
| emit(f,"\n"); |
| } |
| |
| // If q2 is a register but q1 isn't we could reverse the comparison, but would then have to reverse |
| // the subsequent conditional branch. |
| // FIXME - can also reverse if one value is cached |
| |
| if (!isreg(q1)) { |
| if(isreg(q2)) { // Reverse the test. |
| emit_objtoreg(f, &p->q1, t,tmp); |
| q1reg=q2reg; |
| reversecmp=1; |
| } else { // Neither object is in a register, so load q1 into t1 and q2 into tmp. |
| emit_objtoreg(f, &p->q1, t,t1); |
| cleartempobj(f,t1); |
| q1reg = t1; |
| emit_objtoreg(f, &p->q2, t,tmp); |
| } |
| } |
| else |
| emit_objtoreg(f, &p->q2, t,tmp); |
| if ((!(q1typ(p) & UNSIGNED)) && (!(q2typ(p) & UNSIGNED))) { // If we have a mismatch of signedness we treat as unsigned. |
| int nextop=p->next->code; // Does the sign matter for the branch being done? |
| if(nextop==FREEREG) |
| nextop=p->next->next->code; |
| if((nextop!=BEQ) && (nextop!=BNE)) |
| emit(f, "\tsgn\n"); // Signed comparison |
| } |
| emit(f, "\tcmp\t%s\n", regnames[q1reg]); |
| continue; |
| } |
| |
| // Division and modulo |
| if ((c == MOD) || (c == DIV)) { |
| int targetreg=zreg; |
| int doneq2=0; |
| // FIXME - do we need to use switch_IC here? |
| if(DBGMSG) |
| emit(f, "\t\t\t\t\t\t//Call division routine\n"); |
| |
| // determine here whether R1 and R2 really need saving - may not be in use, or may be the target register. |
| if(regs[t2] && zreg!=t2) |
| { |
| emit(f, "\tmt\t%s\n\tstdec\t%s\n", regnames[t2], regnames[sp]); |
| cleartempobj(f,tmp); |
| pushed+=4; |
| } |
| if(regs[t2+1] && zreg!=(t2+1)) |
| { |
| emit(f, "\tmt\t%s\n\tstdec\t%s\n", regnames[t2 + 1], regnames[sp]); |
| cleartempobj(f,tmp); |
| pushed += 4; |
| } |
| // q1 must be written to t2, q2 must be written to t2+2 |
| // if q2 starts in t2 we have to avoid overwriting it. |
| |
| // If q1 is already in t2, q2 can't be, so we don't need to worry about swapping |
| if(!isreg(q1) || q1reg!=t2) |
| { |
| emit_objtoreg(f, &p->q1, t,tmp); |
| |
| // Need to make sure we're not about to overwrite the other operand! |
| if(isreg(q2) && q2reg==t2) |
| { |
| emit(f,"\texg\t%s\n",regnames[t2]); |
| emit(f,"\tmr\t%s\n",regnames[t2+1]); |
| doneq2=1; |
| } |
| else |
| emit(f, "\tmr\t%s\n", regnames[t2]); |
| } |
| if(!doneq2 && (!isreg(q2) || q2reg!=t2+1)) |
| { |
| emit_objtoreg(f, &p->q2, t,tmp); |
| emit(f, "\tmr\t%s\n", regnames[t2 + 1]); |
| } |
| cleartempobj(f,t1); |
| cleartempobj(f,t2); |
| |
| if ((!(q1typ(p) & UNSIGNED)) && (!(q2typ(p) & UNSIGNED))) // If we have a mismatch of signedness we treat as unsigned. |
| emit(f, "\t.lipcrel\t_div_s32bys32\n"); |
| else |
| emit(f, "\t.lipcrel\t_div_u32byu32\n"); |
| emit(f, "\tadd\t%s\n", regnames[pc]); |
| |
| // If the next IC is SetReturn from the same register we can skip saving the result. |
| if(next_setreturn(p,zreg)) |
| { |
| emit(f,"\t\t\t\t\t\t// Skipping save_result...\n"); |
| targetreg=t1; |
| } |
| |
| if (c == MOD) |
| { |
| if(targetreg!=t2) |
| emit(f, "\tmt\t%s\n\tmr\t%s\n", regnames[t2], regnames[zreg]); |
| } |
| else |
| { |
| if(targetreg!=t1) |
| emit(f, "\tmt\t%s\n\tmr\t%s\n", regnames[t1], regnames[zreg]); |
| } |
| |
| if(regs[t2+1] && zreg!=(t2+1)) |
| { |
| emit(f, "\tldinc\t%s\n\tmr\t%s\n", regnames[sp], regnames[t2+1]); |
| pushed -= 4; |
| } |
| if(regs[t2] && zreg!=t2) |
| { |
| emit(f, "\tldinc\t%s\n\tmr\t%s\n", regnames[sp], regnames[t2]); |
| pushed -= 4; |
| } |
| |
| cleartempobj(f,tmp); |
| cleartempobj(f,t1); |
| |
| // Target not guaranteed to be a register. |
| save_result(f, p); |
| |
| continue; |
| } |
| |
| // Remaining arithmetic and bitwise operations |
| |
| if ((c >= OR && c <= AND) || (c >= LSHIFT && c <= MULT)) { |
| if(DBGMSG) |
| emit(f, "\t\t\t\t\t\t// (bitwise/arithmetic) "); |
| if(DBGMSG) |
| emit(f, "\t//ops: %d, %d, %d\n", q1reg, q2reg, zreg); |
| if(p->q1.am && p->q1.am->type==AM_ADDT) |
| { |
| if(DBGMSG) |
| emit(f,"\t\t\t\t\t\t//Special case - addt\n"); |
| // FIXME - if q2 is already in tmp could reverse this |
| if(p->q2.flags&KONST) |
| { |
| zreg=t1; |
| emit_prepobj(f, &p->z, t, t1, 0); |
| |
| emit_objtoreg(f, &p->q2, t,tmp); |
| emit(f,"\taddt\t%s\n",regnames[p->q1.reg]); |
| settempobj(f,tmp,&p->z,0,0); |
| save_temp(f, p, zreg); |
| obsoletetempobj(f,t1,&p->z,0); |
| // emit(f,"\tmr\t%s\n",regnames[p->z.reg]); |
| } |
| else |
| { |
| zreg=t1; |
| emit_prepobj(f, &p->z, t, t1, 0); |
| |
| emit_objtoreg(f, &p->q1, t,tmp); |
| emit(f,"\taddt\t%s\n",regnames[p->q2.reg]); |
| settempobj(f,tmp,&p->z,0,0); |
| save_temp(f, p, zreg); |
| obsoletetempobj(f,t1,&p->z,0); |
| // emit(f,"\tmr\t%s\n",regnames[p->z.reg]); |
| } |
| continue; |
| } |
| |
| if (involvesreg(q2) && q2reg == zreg) { |
| // printf("Target register and q2 are the same! Attempting a switch...\n"); |
| if (switch_IC(p)) { |
| preload(f,p,1); // refresh q1reg, etc after switching the IC |
| } else { |
| emit(f, |
| "\t\t\t\t\t\t// WARNING - evading q2 and target collision - check code for correctness.\n"); |
| zreg = t1; |
| } |
| } |
| if (involvesreg(q1) && q1reg == zreg) |
| emit(f,"\t\t\t\t\t\t// WARNING - q1 and target collision - check code for correctness.\n"); |
| |
| if (!isreg(q1) || q1reg != zreg) { |
| emit_objtoreg(f, &p->q1, t,zreg); |
| // emit(f, "\tmr\t%s\n", regnames[zreg]); // FIXME - what happens if zreg and q1/2 are the same? |
| } |
| emit_objtoreg(f, &p->q2, t,tmp); |
| if (c >= OR && c <= AND) |
| emit(f, "\t%s\t%s\n", logicals[c - OR], regnames[zreg]); |
| else { |
| if (c == RSHIFT || c==MULT) // Modify right shift operations with appropriate signedness... |
| { |
| // printf("q1typ: %x, q2typ: %x, ztyp: %x\n",q1typ(p),q2typ(p),ztyp(p)); |
| if (!(t & UNSIGNED)) |
| { |
| // Evaluate q1 - if we're dealing with a constant that doesn't have bit 31 set we don't need sgn... |
| if((!(p->typf2 & UNSIGNED) && c==RSHIFT) |
| || (p->q1.flags&(KONST|DREFOBJ)!=KONST) |
| || (val2zmax(&p->q1,p->typf)&0x80000000)) |
| emit(f, "\tsgn\n"); |
| } |
| } |
| emit(f, "\t%s\t%s\n", arithmetics[c - LSHIFT], regnames[zreg]); |
| if(c==MULT) |
| cleartempobj(f,tmp); |
| } |
| settempobj(f,zreg,&p->z,0,0); |
| cleartempobj(f,zreg); |
| save_result(f, p); |
| continue; |
| } |
| printf("Unhandled IC\n"); |
| pric2(stdout, p); |
| ierror(0); |
| } |
| if(function_bottom(f, v, localsize+notyetpopped,firsttail)) |
| firsttail=0; |
| } |
| |
| int shortcut(int code, int typ) |
| { |
| // Only RSHIFT and AND are safe on 832. |
| // So far have seen shortcut requests for |
| // DIV |
| // ADD |
| // RSHIFT |
| // COMPARE |
| // SUB |
| // LSHIFT |
| // AND |
| // MULT |
| // OR |
| |
| // printf("Evaluating shortcut for code %d, type %x\n",code,typ); |
| if(code==RSHIFT) |
| return(1); |
| if(code==AND) |
| return(1); |
| |
| return 0; |
| } |
| |
| int reg_parm(struct reg_handle *m, struct Typ *t, int vararg, struct Typ *d) |
| { |
| int f; |
| f = t->flags & NQ; |
| if(is_varargs(d)) /* Disallow register parameters for varargs functions */ |
| return(0); |
| |
| if (f <= LONG || f == POINTER) { |
| if (m->gregs >= REGPARM_COUNT) |
| return 0; |
| else |
| return FIRST_GPR + 1 + m->gregs++; |
| } |
| if (ISFLOAT(f)) { |
| return(0); |
| /* if (m->fregs >= 0) |
| return 0; |
| else |
| return FIRST_FPR + 2 + m->fregs++; |
| */ |
| } |
| return 0; |
| } |
| |
| int iscomment(char *str) |
| { |
| char c; |
| while(c=*str++) |
| { |
| if(!c || c=='\n' || c=='/') |
| return(1); |
| if(c!=' '&&c!='\t') |
| return(0); |
| } |
| return(1); |
| } |
| |
| |
| int emit_peephole(void) |
| { |
| int i; |
| int havemr=0; |
| int havemt=0; |
| int havestore=0; |
| int haveload=0; |
| int loadidx=0; |
| i=emit_f; |
| |
| while(i!=emit_l) |
| { |
| int reg,reg2; |
| if(sscanf(emit_buffer[i],"\tmr\tr%d",®)==1) |
| { |
| if(havemt && reg==reg2) |
| { |
| strcpy(emit_buffer[i],"\t//mr\n"); |
| return(1); |
| } |
| reg2=reg; |
| havemr=1; |
| havemt=0; |
| } |
| else if(sscanf(emit_buffer[i],"\tmt\tr%d",®)==1) |
| { |
| if(havemr && reg==reg2) |
| { |
| strcpy(emit_buffer[i],"\t//mt\n"); |
| return(1); |
| } |
| reg2=reg; |
| havemr=0; |
| havemt=1; |
| } |
| else if(sscanf(emit_buffer[i],"\tst\tr%d",®)==1) |
| { |
| havemr=havemt=0; |
| havestore=1; |
| } |
| else if(sscanf(emit_buffer[i],"\tld\tr%d",®2)==1 && havestore) |
| { |
| havemr=havemt=0; |
| if(reg==reg2 && reg==6) /* Only stack ops - others would be risky due to potential hardware registers. */ |
| { |
| loadidx=i; |
| haveload=1; |
| // printf("Found matching load directive, r%d\n",reg); |
| // strcpy(emit_buffer[i],"\t//nop\n"); |
| // return(1); |
| } |
| } |
| else if(!iscomment(emit_buffer[i])) /* Check that the next instruction isn't "cond" */ |
| { |
| havemr=havemt=0; |
| if(haveload && strncmp(emit_buffer[i],"\tcond",5)) /* If not, we're OK to zero out the load */ |
| { |
| strcpy(emit_buffer[loadidx],"\t//nop\n"); |
| return(1); |
| } |
| else |
| { |
| havestore=haveload=0; |
| } |
| } |
| i=(i+1)%EMIT_BUF_DEPTH; |
| } |
| return 0; |
| } |
| |
| |
| int handle_pragma(const char *s) |
| { |
| return(0); |
| } |
| |
| void cleanup_cg(FILE * f) |
| { |
| } |
| |
| void cleanup_db(FILE * f) |
| { |
| if (f) |
| section = -1; |
| } |