Correct a subtle bug in the ia32 backend: Sub(x, x) triggered that the Neg+Add trick...

[libfirm] / ir / be / beabi.c

diff --git a/ir/be/beabi.c b/ir/be/beabi.c
index 9a2bdf3..f4fe80d 100644 (file)
--- a/ir/be/beabi.c
+++ b/ir/be/beabi.c
@@ -888,7 +888,11 @@ static ir_node *adjust_alloc(be_abi_irg_t *env, ir_node *alloc, ir_node *curr_sp
        dbg_info *dbg;
 
        const ir_edge_t *edge;
-       ir_node *new_alloc, *size, *addr, *ins[2];
+       ir_node *new_alloc;
+       ir_node *count;
+       ir_node *size;
+       ir_node *addr;
+       ir_node *ins[2];
        unsigned stack_alignment;
 
        assert(get_Alloc_where(alloc) == stack_alloc);
@@ -923,16 +927,18 @@ static ir_node *adjust_alloc(be_abi_irg_t *env, ir_node *alloc, ir_node *curr_sp
                return curr_sp;
        }
 
-       dbg  = get_irn_dbg_info(alloc);
-       size = get_Alloc_size(alloc);
+       dbg   = get_irn_dbg_info(alloc);
+       count = get_Alloc_count(alloc);
 
-       /* we might need to multiply the size with the element size */
+       /* we might need to multiply the count with the element size */
        if (type != firm_unknown_type && get_type_size_bytes(type) != 1) {
-               ir_mode *mode = get_irn_mode(size);
+               ir_mode *mode = get_irn_mode(count);
                tarval *tv    = new_tarval_from_long(get_type_size_bytes(type),
                                                     mode);
                ir_node *cnst = new_rd_Const(dbg, irg, tv);
-               size          = new_rd_Mul(dbg, block, size, cnst, mode);
+               size          = new_rd_Mul(dbg, block, count, cnst, mode);
+       } else {
+               size = count;
        }
 
        /* The stack pointer will be modified in an unknown manner.