From 1446b543ae54643d904c15525fa75ab580b9ea23 Mon Sep 17 00:00:00 2001
From: Joe Soroka <gits@joesoroka.com>
Date: Sat, 9 Apr 2011 22:52:25 -0700
Subject: [PATCH] VLA fix [3/3]: store VLA sizeofs in anonymous runtime stack
 vars

---
 tcc.h    |  1 -
 tccgen.c | 55 ++++++++++++++++++++++---------------------------------
 2 files changed, 22 insertions(+), 34 deletions(-)

diff --git a/tcc.h b/tcc.h
index be53b657..fcbfadcd 100644
--- a/tcc.h
+++ b/tcc.h
@@ -224,7 +224,6 @@ typedef struct Sym {
     union {
         long c;    /* associated number */
         int *d;   /* define token stream */
-        SValue *s; /* associated stack value */
     };
     CType type;    /* associated type */
     union {
diff --git a/tccgen.c b/tccgen.c
index b55af88d..bc9b24fb 100644
--- a/tccgen.c
+++ b/tccgen.c
@@ -2036,22 +2036,9 @@ ST_FUNC int type_size(CType *type, int *a)
 ST_FUNC void vla_runtime_type_size(CType *type, int *a)
 {
     if (type->t & VT_VLA) {
-        Sym *s;
-
-        s = type->ref;
-        vla_runtime_type_size(&s->type, a);
-        vpushv(s->s);
-        if ((vtop->r & (VT_SYM|VT_LVAL|VT_VALMASK)) != VT_CONST) {
-            gv_dup();
-            vswap();
-            vpop();
-        }
-        gen_op('*');
+        vset(&int_type, VT_LOCAL|VT_LVAL, type->ref->c);
     } else {
-        int size;
-
-        size = type_size(type, a);
-        vpushi(size);
+        vpushi(type_size(type, a));
     }
 }
 
@@ -3170,8 +3157,6 @@ static void post_type(CType *type, AttributeDef *ad)
         type->t = VT_FUNC;
         type->ref = s;
     } else if (tok == '[') {
-        SValue *last_vtop = NULL;
-
         /* array definition */
         next();
         if (tok == TOK_RESTRICT1)
@@ -3182,14 +3167,12 @@ static void post_type(CType *type, AttributeDef *ad)
             gexpr();
             if ((vtop->r & (VT_VALMASK | VT_LVAL | VT_SYM)) == VT_CONST) {
                 n = vtop->c.i;
-                last_vtop = vtop;
                 if (n < 0)
                     error("invalid array size");
             } else {
                 if (!is_integer_btype(vtop->type.t & VT_BTYPE))
                     error("size of variable length array should be an integer");
                 t1 = VT_VLA;
-                last_vtop = vtop;
             }
         }
         skip(']');
@@ -3197,15 +3180,23 @@ static void post_type(CType *type, AttributeDef *ad)
         post_type(type, ad);
         t1 |= type->t & VT_VLA;
         
+        if (t1 & VT_VLA) {
+            loc -= type_size(&int_type, &align);
+            loc &= -align;
+            n = loc;
+
+            vla_runtime_type_size(type, &align);
+            gen_op('*');
+            vset(&int_type, VT_LOCAL|VT_LVAL, loc);
+            vswap();
+            vstore();
+        }
+        if (n != -1)
+            vpop();
+                
         /* we push an anonymous symbol which will contain the array
            element type */
         s = sym_push(SYM_FIELD, type, 0, n);
-        if (t1 & VT_VLA) {
-            s->s = last_vtop; // That's ok, we don't need n with VLA
-        } else {
-            if (n >= 0)
-                vpop();
-        }
         type->t = (t1 ? VT_VLA : VT_ARRAY) | VT_PTR;
         type->ref = s;
     }
@@ -3741,10 +3732,7 @@ ST_FUNC void unary(void)
         } else {
             r = s->r;
         }
-        if (s->type.t & VT_VLA)
-            vpushv(s->s);
-        else
-            vset(&s->type, r, s->c);
+        vset(&s->type, r, s->c);
         /* if forward reference, we must point to s */
         if (vtop->r & VT_SYM) {
             vtop->sym = s;
@@ -4895,6 +4883,10 @@ static void decl_initializer(CType *type, Section *sec, unsigned long c,
         /* return value */
         retcval.i = 0;
         vsetc(type, REG_IRET, &retcval);
+        vset(type, VT_LOCAL|VT_LVAL, c);
+        vswap();
+        vstore();
+        vpop();
     } else if (type->t & VT_ARRAY) {
         s = type->ref;
         n = s->c;
@@ -5132,7 +5124,6 @@ static void decl_initializer_alloc(CType *type, AttributeDef *ad, int r,
     ParseState saved_parse_state = {0};
     TokenString init_str;
     Section *sec;
-    Sym *vla = NULL;
     Sym *flexible_array;
 
     flexible_array = NULL;
@@ -5233,7 +5224,7 @@ static void decl_initializer_alloc(CType *type, AttributeDef *ad, int r,
 #endif
         if (v) {
             /* local variable */
-            vla = sym_push(v, type, r, addr);
+            sym_push(v, type, r, addr);
         } else {
             /* push local reference */
             vset(type, r, addr);
@@ -5348,8 +5339,6 @@ static void decl_initializer_alloc(CType *type, AttributeDef *ad, int r,
     }
     if (has_init || (type->t & VT_VLA)) {
         decl_initializer(type, sec, addr, 1, 0);
-        if (type->t & VT_VLA)
-            vla->s = vtop;
         /* restore parse state if needed */
         if (init_str.str) {
             tok_str_free(init_str.str);
-- 
2.11.4.GIT