Win64 struct passing

dlang · Aug 25, 2012 · 665048a · 665048a
1 parent e69ff99
commit 665048a
Show file tree

Hide file tree

Showing 2 changed files with 35 additions and 23 deletions.
diff --git a/src/backend/cod1.c b/src/backend/cod1.c
@@ -2538,12 +2538,13 @@ code *cdfunc(elem *e,regm_t *pretregs)
     for (int i = np; --i >= 0;)
     {
         elem *ep = parameters[i].e;
-        //printf("[%d] size = %u, numpara = %d ", i, paramsize(ep, stackalign), numpara); WRTYxx(ep->Ety); printf("\n");
+        unsigned psize = paramsize(ep, stackalign);
+        //printf("[%d] size = %u, numpara = %d ", i, psize, numpara); WRTYxx(ep->Ety); printf("\n");
         if (fpr.alloc(ep->ET, ep->Ety, &parameters[i].reg, &parameters[i].reg2))
         {
             if (config.exe == EX_WIN64)
-            {   numpara += REGSIZE;             // allocate stack space for it anyway
-                assert(paramsize(ep, stackalign) <= REGSIZE);
+            {   assert(psize <= REGSIZE);
+                numpara += REGSIZE;             // allocate stack space for it anyway
             }
             continue;   // goes in register, not stack
         }
@@ -2557,7 +2558,7 @@ code *cdfunc(elem *e,regm_t *pretregs)
             parameters[i].numalign = newnumpara - numpara;
             numpara = newnumpara;
         }
-        numpara += paramsize(ep,stackalign);
+        numpara += psize;
     }
 
     if (config.exe == EX_WIN64)
@@ -2587,6 +2588,11 @@ code *cdfunc(elem *e,regm_t *pretregs)
         stackpushsave += numalign;
     }
     assert(stackpush == stackpushsave);
+    if (config.exe == EX_WIN64)
+    {
+        //printf("np = %d, numpara = %d, stackpush = %d\n", np, numpara, stackpush);
+        assert(numpara == ((np < 4) ? 4 * REGSIZE : np * REGSIZE));
+    }
 
     int regsaved[XMM7 + 1];
     memset(regsaved, -1, sizeof(regsaved));
@@ -2749,9 +2755,7 @@ code *cdfunc(elem *e,regm_t *pretregs)
     if (config.exe == EX_WIN64)
     {   // Allocate stack space for four entries anyway
         // http://msdn.microsoft.com/en-US/library/ew5tede7(v=vs.80)
-        unsigned sz = 4 * REGSIZE;
-        if (stackpush - stackpushsave < sz)
-        {   sz -= stackpush - stackpushsave;
+        {   unsigned sz = 4 * REGSIZE;
             c = cod3_stackadj(c, sz);
             c = genadjesp(c, sz);
             stackpush += sz;

diff --git a/src/e2ir.c b/src/e2ir.c
@@ -46,7 +46,7 @@ static char __file__[] = __FILE__;      /* for tassert.h                */
 
 typedef ArrayBase<elem> Elems;
 
-elem *addressElem(elem *e, Type *t);
+elem *addressElem(elem *e, Type *t, bool alwaysCopy = false);
 elem *array_toPtr(Type *t, elem *e);
 elem *appendDtors(IRState *irs, elem *er, size_t starti, size_t endi);
 
@@ -55,11 +55,16 @@ elem *appendDtors(IRState *irs, elem *er, size_t starti, size_t endi);
 
 /* If variable var of type typ is a reference
  */
+bool ISREF(Declaration *var, Type *tb)
+{
 #if SARRAYVALUE
-#define ISREF(var, tb) (var->isOut() || var->isRef())
+    return (var->isParameter() && config.exe == EX_WIN64 && var->type->size(0) > REGSIZE)
+            || var->isOut() || var->isRef();
 #else
-#define ISREF(var, tb) ((var->isParameter() && tb->ty == Tsarray) || var->isOut() || var->isRef())
+    return (var->isParameter() && (var->type->toBasetype()->ty == Tsarray || (config.exe == EX_WIN64 && var->type->size(0) > REGSIZE)))
+            || var->isOut() || var->isRef();
 #endif
+}
 
 /************************************
  * Call a function.
@@ -146,6 +151,14 @@ elem *callfunc(Loc loc,
                     goto L1;
                 }
             }
+            if (config.exe == EX_WIN64 && arg->type->size(arg->loc) > REGSIZE)
+            {   /* Copy to a temporary, and make the argument a pointer
+                 * to that temporary.
+                 */
+                ea = arg->toElem(irs);
+                ea = addressElem(ea, arg->type, true);
+                goto L1;
+            }
             ea = arg->toElem(irs);
         L1:
             if (tybasic(ea->Ety) == TYstruct || tybasic(ea->Ety) == TYarray)
@@ -232,13 +245,10 @@ elem *callfunc(Loc loc,
         else
         {
             // make virtual call
-            elem *ev;
-            unsigned vindex;
-
             assert(ethis);
-            ev = el_same(&ethis);
+            elem *ev = el_same(&ethis);
             ev = el_una(OPind, TYnptr, ev);
-            vindex = fd->vtblIndex;
+            unsigned vindex = fd->vtblIndex;
             assert((int)vindex >= 0);
 
             // Build *(ev + vindex * 4)
@@ -336,17 +346,15 @@ if (I32) assert(tysize[TYnptr] == 4);
  * Take address of an elem.
  */
 
-elem *addressElem(elem *e, Type *t)
+elem *addressElem(elem *e, Type *t, bool alwaysCopy)
 {
-    elem **pe;
-
     //printf("addressElem()\n");
 
+    elem **pe;
     for (pe = &e; (*pe)->Eoper == OPcomma; pe = &(*pe)->E2)
         ;
-    if ((*pe)->Eoper != OPvar && (*pe)->Eoper != OPind)
-    {   Symbol *stmp;
-        elem *eeq;
+    if (alwaysCopy || ((*pe)->Eoper != OPvar && (*pe)->Eoper != OPind))
+    {
         elem *e2 = *pe;
         type *tx;
 
@@ -356,8 +364,8 @@ elem *addressElem(elem *e, Type *t)
             tx = t->toCtype();
         else
             tx = type_fake(e2->Ety);
-        stmp = symbol_genauto(tx);
-        eeq = el_bin(OPeq,e2->Ety,el_var(stmp),e2);
+        Symbol *stmp = symbol_genauto(tx);
+        elem *eeq = el_bin(OPeq,e2->Ety,el_var(stmp),e2);
         if (tybasic(e2->Ety) == TYstruct)
         {
             eeq->Eoper = OPstreq;