REFACTOR: move sources to src/

1 files changed, 462 insertions, 0 deletions

diff --git a/src/ir_abi0.c b/src/ir_abi0.c
new file mode 100644
index 0000000..a3687d9
--- /dev/null
+++ b/src/ir_abi0.c
@@ -0,0 +1,462 @@
+#include "ir.h"
+
+/**  This pass adds in ABI arguments/returns register mappings
+ **  and lowers aggregate params/args/returns into scalars
+ **
+ **  invariant: all `call` instructions when doing this pass shall be preceded by
+ **  exactly narg `arg` instructions with no other instructions in between
+ **/
+
+struct abiargsvec { vec_of(struct abiarg); };
+
+static int
+abiret(struct abiarg abiret[2], struct abiargsvec *abiargs, uchar *r2off, int *ni, union irtype retty)
+{
+   short r[2];
+   uchar cls[2];
+   int retreg = 0;
+   retreg = mctarg->abiret(r, cls, r2off, ni, retty);
+   if (retty.isagg) {
+      if (!retreg) {
+         vpush(abiargs, ((struct abiarg) { cls2type(KPTR), .reg = r[1] }));
+         if (r[0] == -1) {
+            memset(abiret, 0, 2*sizeof *abiret);
+         } else {
+            abiret[0].ty = cls2type(KPTR);
+            abiret[0].reg = r[0];
+         }
+      }
+   } else if (retty.cls) {
+      assert(retreg == 1);
+   }
+   for (int i = 0; i < retreg; ++i) {
+      abiret[i].ty = cls2type(cls[i]);
+      abiret[i].isstk = 0;
+      abiret[i].reg = r[i];
+   }
+   return retreg;
+}
+
+static int
+abiarg(struct abiargsvec *abiargs, uchar *r2off, int *ni, int *nf, int *ns, union irtype ty)
+{
+   short r[2];
+   uchar cls[2];
+   int ret = mctarg->abiarg(r, cls, r2off, ni, nf, ns, ty);
+   if (!ret) { /* in stack */
+      vpush(abiargs, ((struct abiarg) { ty, .isstk = 1, .stk = r[0] }));
+   } else if (ret == 1 && ty.isagg && cls[0] == KPTR) { /* aggregate by pointer */
+      vpush(abiargs, ((struct abiarg) { cls2type(cls[0]), .reg = r[0] }));
+   } else { /* by regs */
+      vpush(abiargs, ((struct abiarg) { cls2type(cls[0]), .reg = r[0] }));
+      if (ret == 2)
+         vpush(abiargs, ((struct abiarg) { cls2type(cls[1]), .reg = r[1] }));
+   }
+   return ret;
+}
+
+static struct instr
+copyparam(struct function *fn, int *curi, int param, struct abiarg abi)
+{
+   struct instr par = mkinstr(Oparam, abi.ty.cls, mkref(RICON, param), mktyperef(abi.ty));
+   if (!abi.isstk) { /* reg */
+      assert(!abi.ty.isagg);
+      return par;
+   }
+   par.r = mktyperef((union irtype){.cls = KPTR});
+   if (!abi.ty.isagg) { /* scalar in stack */
+      enum op ld;
+      par.cls = KPTR;
+      if (abi.ty.cls == KPTR) abi.ty.cls = siz2intcls[cls2siz[abi.ty.cls]];
+      switch (abi.ty.cls) {
+      default: assert(0);
+      case KI32: ld = Oloads32; break;
+      case KI64: ld = Oloadi64; break;
+      case KF32: ld = Oloadf32; break;
+      case KF64: ld = Oloadf64; break;
+      }
+      return mkinstr(ld, abi.ty.cls, insertinstr(fn->entry, (*curi)++, par));
+   } else { /* aggregate in stack */
+      par.cls = KPTR;
+      return par;
+   }
+}
+
+static void
+patchparam(struct function *fn, int *curi, int *param, int tydat, int nabi, struct abiarg abi[2], uchar r2off)
+{
+   struct block *blk = fn->entry;
+   assert(in_range(nabi,1,2));
+
+   for (; *curi < blk->ins.n; ++*curi) {
+      struct instr *ins = &instrtab[blk->ins.p[*curi]];
+      if (ins->op != Oparam) continue;
+      assert(ins->r.t == RTYPE
+            && ins->r.i == (tydat < 0 ? abi[0].ty : (union irtype){.isagg=1, .dat=tydat}).bits);
+      if (abi[0].ty.isagg || tydat < 0) {
+         /* aggregate in stack or scalar, just copy */
+         assert(nabi == 1);
+         *ins = copyparam(fn, curi, *param, abi[0]);
+      } else { /* aggregate in registers, materialize */
+         union ref alloc, r[2];
+         struct instr st;
+         const struct typedata *td;
+         uint nalloc;
+         uint align;
+
+         assert(tydat >= 0);
+         td = &typedata[tydat];
+         assert(td->siz <= 16 && td->align <= 16);
+         align = td->siz <= 4 ? 4 : alignup(td->align, 8);
+         nalloc = td->siz/align + (td->siz%align != 0);
+         *ins = mkinstr(Oalloca1 + ilog2(align), KPTR, mkref(RICON, nalloc));
+         alloc = mkref(RTMP, ins - instrtab);
+         r[0] = insertinstr(blk, ++*curi, copyparam(fn, NULL, *param, abi[0]));
+         if (nabi > 1)
+            r[1] = insertinstr(blk, ++*curi, copyparam(fn, NULL, ++*param, abi[1]));
+         /* transform
+          *  %x = copy %p
+          * into
+          *  %x = alloca...
+          *  store* %x, %a
+          *  store* %x + N, %b
+          */
+         st = mkinstr(cls2store[abi[0].ty.cls], 0, alloc, r[0]);
+         insertinstr(blk, ++*curi, st);
+         if (nabi > 1) {
+            struct instr tmp = mkinstr(Oadd, KPTR, alloc, mkref(RICON, r2off));
+            st = mkinstr(cls2store[abi[1].ty.cls], 0, insertinstr(blk, ++*curi, tmp), r[1]);
+            insertinstr(blk, ++*curi, st);
+         }
+      }
+      ++*param;
+      ++*curi;
+      break;
+   }
+}
+
+static void
+load2regs(union ref out[2], union irtype typ, union ref src, int nabi, struct abiarg abi[2], uchar r2off, struct block *blk, int *curi)
+{
+   uint align = typedata[typ.dat].align;
+   uint siz = typedata[typ.dat].siz;
+   if (src.t == RTMP && oisalloca(instrtab[src.i].op)) {
+      /* use actual alignment as opposed to min required type alignment */
+      uint aalign = 1 << (instrtab[src.i].op - Oalloca1);
+      assert(aalign >= align);
+      align = aalign;
+   }
+   /* deconstruct into
+    * %a = load* %x
+    * (%b = load* %x + N)
+    */
+   /* XXX this generates pretty bad code for small-alignment structs even on platforms where unaligned loads are available.. */
+   if (align >= 4) {
+      for (int i = 0; i < nabi; ++i) {
+         struct instr ins = {0};
+         union ref temp;
+         switch (ins.cls = abi[i].ty.cls) {
+         default: assert(0);
+         case KI32: ins.op = Oloadu32; break;
+         case KI64: ins.op = Oloadi64; break;
+         case KF32: ins.op = Oloadf32; break;
+         case KF64: ins.op = Oloadf64; break;
+         }
+         if (i == 0)
+            ins.l = src;
+         else {
+            struct instr adr = mkinstr(Oadd, KPTR, src, mkref(RICON, r2off));
+            ins.l = insertinstr(blk, (*curi)++, adr);
+         }
+         temp = insertinstr(blk, (*curi)++, ins);
+         //insertinstr(blk, (*curi)++, mkarginstr(abi[i].ty, temp));
+         out[i] = temp;
+      }
+   } else {
+      for (int i = 0; i < nabi; ++i) {
+         struct instr ld = {0};
+         union ref reg, temp;
+         uint n = cls2siz[abi[i].ty.cls] / align;
+         assert(n > 0);
+         ld.op = Oloadu8 + ilog2(align)*2;
+         ld.cls = abi[i].ty.cls;
+         for (int o = 0; o < n && (i*cls2siz[ld.cls])+o*align < siz; ++o) {
+            if (i+o == 0)
+               ld.l = src;
+            else {
+               struct instr adr = mkinstr(Oadd, KPTR, src, mkref(RICON, (i == 0 ? 0 : r2off) + o*align));
+               ld.l = insertinstr(blk, (*curi)++, adr);
+            }
+            temp = insertinstr(blk, (*curi)++, ld);
+            if (o > 0) {
+               union ref t = insertinstr(blk, (*curi)++, mkinstr(Oshl, ld.cls, temp, mkref(RICON, o*align*8)));
+               reg = insertinstr(blk, (*curi)++, mkinstr(Oior, ld.cls, reg, t));
+            } else {
+               reg = temp;
+            }
+         }
+         //insertinstr(blk, arginst++, mkarginstr(abi[i].ty, reg));
+         out[i] = reg;
+      }
+   }
+}
+
+static int
+patcharg(struct block *blk, int *icall, struct call *call,
+         int argidx, int nabi, struct abiarg abi[2], uchar r2off)
+{
+   int arginst = *icall - (call->narg - argidx);
+   struct instr *arg = &instrtab[blk->ins.p[arginst]];
+   assert(arg->op == Oarg && arg->l.t == RTYPE);
+   if (ref2type(arg->l).isagg) { /* aggregate argument */
+      if (abi[0].ty.isagg) {  /* aggregate in stack */
+         /* XXX do this better.. */
+         /* ptr %dst = arg <stk dst> */
+         /* (blit %dst, %src) */
+         union ref dst = mkref(RTMP, arg - instrtab);
+         uint align = typedata[abi->ty.dat].align, siz = typedata[abi->ty.dat].siz;
+         union ref src = arg->r;
+         if (src.t == RTMP && oisalloca(instrtab[src.i].op)) {
+            align = 1 << (instrtab[src.i].op - Oalloca1);
+         }
+         assert(align <= 8);
+         arg->cls = KPTR;
+         arg->r = mkref(RICON, abi->stk);
+         for (uint off = 0; off < siz; off += align) {
+            union ref sadr = off == 0 ? src : insertinstr(blk, ++arginst, mkinstr(Oadd, KPTR, src, mkref(RICON, off)));
+            union ref tmp = insertinstr(blk, ++arginst, mkinstr(Oloads8+2*ilog2(align), align < 8 ? KI32 : KI64, sadr));
+            union ref dadr = off == 0 ? dst : insertinstr(blk, ++arginst, mkinstr(Oadd, KPTR, dst, mkref(RICON, off)));
+            insertinstr(blk, ++arginst, mkinstr(Ostorei8+ilog2(align), 0, dadr, tmp));
+         }
+         *icall = arginst + (call->narg - argidx);
+         return 1;
+      } else if (abi[0].ty.cls == KPTR) { /* aggregate by pointer */
+         arg->cls = KPTR;
+         return 1;
+      } else { /* aggregate in registers */
+         union ref r[2];
+         delinstr(blk, arginst);
+         load2regs(r, ref2type(arg->l), arg->r, nabi, abi, r2off, blk, &arginst);
+         for (int i = 0; i < nabi; ++i)
+            insertinstr(blk, arginst++, mkinstr(Oarg, 0, mktyperef(abi[i].ty), r[i]));
+         *icall = arginst + (call->narg - argidx - 1);
+         return nabi;
+      }
+   } else { /* normal scalar argument */
+      return 1;
+   }
+}
+void
+abi0_call(struct function *fn, struct instr *ins, struct block *blk, int *curi)
+{
+   union ref retmem;
+   struct abiarg abiargsbuf[32];
+   struct abiargsvec abiargs = {VINIT(abiargsbuf, countof(abiargsbuf))};
+   bool sretarghidden = 0;
+   int ni, nf, ns, vararg, nret = 0;
+   struct call *call = &calltab.p[ins->r.i];
+
+   vararg = call->vararg;
+   ni = nf = ns = 0;
+   assert(!ins->cls == !call->ret.bits);
+   nret = abiret(call->abiret, &abiargs, &call->r2off, &ni, call->ret);
+   if (call->ret.isagg) { /* adjust struct return */
+      union irtype retty = call->ret;
+      struct typedata *td = &typedata[retty.dat];
+      uint align = td->align, ralign;
+      struct instr alloca;
+      int ialloca;
+      for (int i = 0; i < nret; ++i)
+         align = align < (ralign = cls2siz[call->abiret[i].ty.cls]) ? ralign : align;
+      alloca = mkalloca(td->siz, align);
+
+      sretarghidden = ni == 0;
+      /* swap alloca and call temps so users of original call point to alloca */
+      retmem = insertinstr(blk, ialloca = (*curi)++ - call->narg, *ins);
+      *ins = alloca;
+      blk->ins.p[ialloca] = ins - instrtab;
+      blk->ins.p[*curi] = retmem.i;
+      ins = &instrtab[retmem.i];
+      retmem.i = blk->ins.p[ialloca];
+
+      if (!nret) /* hidden pointer argument */
+         insertinstr(blk, (*curi)++ - call->narg,
+                     mkinstr(Oarg, 0, mktyperef((union irtype){.cls=KPTR}), retmem));
+   }
+
+   /* adjust args */
+   for (int i = 0, i2 = ni + sretarghidden; i < call->narg; ++i) {
+      int arginst = *curi - (call->narg - i);
+      struct instr *arg = &instrtab[blk->ins.p[arginst]];
+      union irtype pty = ref2type(arg->l);
+      uchar r2off;
+      int first = abiargs.n;
+      int ret = abiarg(&abiargs, &r2off, &ni, &nf, &ns, pty);
+      ret = patcharg(blk, curi, call, i, ret, &abiargs.p[first], r2off);
+      if (call->vararg == i) vararg = i2;
+      i2 += ret;
+   }
+   call->argstksiz = ns;
+   /* adjust return */
+   if (call->ret.isagg) {
+      ins->cls = 0;
+      if (!nret) { /* hidden pointer argument */
+         ins->cls = 0;
+         if (!call->abiret[0].isstk) {
+            /* the result location pointer is also returned by the callee, e.g. in x86 */
+            ins->cls = KPTR;
+            ++nret;
+            /* even if this is not used, the register copy
+             * must be emitted for the register allocator to know */
+         }
+      } else { /* aggregate returned in regs */
+         union ref r[2];
+         struct instr ret2;
+         assert(in_range(nret, 1, 2));
+         ins->cls = call->abiret[0].ty.cls;
+         r[0] = mkref(RTMP, ins - instrtab);
+         if (nret == 2) {
+            ret2 = mkinstr(Ocall2r, call->abiret[1].ty.cls, r[0]);
+            r[1] = insertinstr(blk, ++*curi, ret2);
+         }
+         for (int i = 0; i < nret; ++i) {
+            struct instr store = { cls2store[call->abiret[i].ty.cls] };
+            if (i == 0) {
+               store.l = retmem;
+            } else {
+               struct instr addr = mkinstr(Oadd, KPTR, retmem, mkref(RICON, call->r2off));
+               store.l = insertinstr(blk, ++*curi, addr);
+            }
+            store.r = r[i];
+            insertinstr(blk, ++*curi, store);
+         }
+      }
+   }
+
+   if (call->ret.isagg) call->ret = (union irtype){0};
+   call->vararg = vararg;
+   call->abiarg = alloccopy(fn->arena, abiargs.p, abiargs.n * sizeof(struct abiarg), 0);
+   call->narg = abiargs.n;
+   vfree(&abiargs);
+}
+
+void
+abi0(struct function *fn)
+{
+   struct abiarg abiargsbuf[32];
+   uint nparam = typedata[fn->fnty.dat].nmemb;
+   const union type *paramty = typedata[fn->fnty.dat].param;
+   struct abiargsvec abiargs = {VINIT(abiargsbuf, countof(abiargsbuf))};
+   int rvovar = -1;
+   int ni = 0, nf = 0, ns = 0, istart = 0;
+   uchar r2off;
+   struct block *blk;
+   union ref sret = {0};
+
+   FREQUIRE(FNUSE);
+
+   if (fn->retty.t == TYVOID) {
+      fn->nabiret = 0;
+   } else {
+      fn->nabiret = abiret(fn->abiret, &abiargs, &r2off, &ni, mkirtype(fn->retty));
+      if (!fn->nabiret && isagg(fn->retty)) { /* ret agg by hidden pointer */
+         struct instr param = copyparam(fn, NULL, 0, abiargs.p[0]);
+         sret = insertinstr(fn->entry, 0, param);
+         ++istart;
+         /* increment real param ordinals */
+         for (int i = 1; i < fn->entry->ins.n; ++i) {
+            struct instr *ins = &instrtab[fn->entry->ins.p[i]];
+            if (ins->op == Oparam) ++ins->l.i;
+         }
+      }
+   }
+
+   /* adjust params */
+   for (int i = 0, param = abiargs.n; i < nparam; ++i) {
+      union irtype pty = mkirtype(paramty[i]);
+      int first = abiargs.n;
+      uchar r2off;
+      int ret = abiarg(&abiargs, &r2off, &ni, &nf, &ns, pty);
+      patchparam(fn, &istart, &param, pty.isagg ? pty.dat : -1, ret+!ret, &abiargs.p[first], r2off);
+   }
+   fn->abiarg = alloccopy(fn->arena, abiargs.p, abiargs.n * sizeof *abiargs.p, 0);
+   fn->nabiarg = abiargs.n;
+   vfree(&abiargs);
+
+   if (!fn->nabiret && isagg(fn->retty)) {
+      /* for structures returned by hidden pointer argument,
+       * if all return instrs return local var X, make X point to the result location,
+       * (return value optimization (RVO)) */
+      blk = fn->entry;
+      do {
+         union ref arg = blk->jmp.arg[0];
+         if (blk->jmp.t != Jret) continue;
+         if (!arg.bits) continue;
+         if (arg.t != RTMP || !oisalloca(instrtab[arg.i].op)) {
+            rvovar = -1;
+            break;
+         }
+         if (rvovar == -1) {
+            rvovar = arg.i;
+         } else if (arg.i != rvovar) {
+            rvovar = -1;
+            break;
+         }
+      } while ((blk = blk->lnext) != fn->entry);
+      if (rvovar != -1)
+         instrtab[rvovar] = mkinstr(Ocopy, KPTR, sret);
+   }
+
+   blk = fn->entry->lnext;
+   int id = 1;
+   do {
+      /* adjust vaargs and calls */
+      for (int iinstr = 0; iinstr < blk->ins.n; ++iinstr) {
+         struct instr *ins = &instrtab[blk->ins.p[iinstr]];
+         if (ins->op == Ovastart) mctarg->vastart(fn, blk, &iinstr);
+         else if (ins->op == Ovaarg) mctarg->vaarg(fn, blk, &iinstr);
+         else if (ins->op == Ocall) abi0_call(fn, ins, blk, &iinstr);
+      }
+
+      /* adjust returns */
+      if (isagg(fn->retty) && blk->jmp.t == Jret && blk->jmp.arg[0].bits) {
+         assert(!blk->jmp.arg[1].bits);
+         if (fn->nabiret) { /* aggregate return in register(s) */
+            union ref r[2];
+            int curi = blk->ins.n;
+            load2regs(r, mkirtype(fn->retty), blk->jmp.arg[0], fn->nabiret, fn->abiret, r2off, blk, &curi);
+            for (int i = 0; i < fn->nabiret; ++i) {
+               blk->jmp.arg[i] = r[i];
+               adduse(blk, USERJUMP, r[i]);
+            }
+         } else {
+            /* aggregate return (arg[0] is pointer to return value) */
+            if (rvovar == -1) {
+               /* blit %sret, %arg */
+               union irtype typ = mkirtype(fn->retty);
+               insertinstr(blk, blk->ins.n, mkarginstr(typ, sret));
+               insertinstr(blk, blk->ins.n, mkarginstr(typ, blk->jmp.arg[0]));
+               insertinstr(blk, blk->ins.n, mkintrin(INstructcopy, 0, 2));
+            } else assert(blk->jmp.arg[0].bits == mkref(RTMP, rvovar).bits);
+            if (fn->abiret[0].ty.cls) {
+               blk->jmp.arg[0] = rvovar == -1 ? sret : mkref(RTMP, rvovar);
+               adduse(blk, USERJUMP, blk->jmp.arg[0]);
+            }
+            else memset(blk->jmp.arg, 0, sizeof blk->jmp.arg);
+         }
+      }
+      blk->id = id++;
+   } while ((blk = blk->lnext) != fn->entry);
+
+
+   /* vaargs might break these */
+   if (!(fn->prop & FNUSE)) filluses(fn);
+   fn->prop &= ~(FNBLKID | FNRPO);
+
+   if (ccopt.dbg.a) {
+      bfmt(ccopt.dbgout, "<< After abi0 >>\n");
+      irdump(fn);
+   }
+}
+
+/* vim:set ts=3 sw=3 expandtab: */