I'm trying to get:
void foo() {
int rowfraclo[2];
rowfraclo[1] = 42;
asm ("movd mm6, %a0" : : "p" (rowfraclo+1));
}
to generate:
movd mm6, -4(%ebp)
at -O0. Currently we generate:
leal -8(%ebp), %eax
addl $4, %eax
movd mm6, (%eax)
With the below patch (still running the testsuite) I can get the
compiler to generate that code. So, the question is how better can I
do this?
Doing diffs in .:
--- ./expr.c.~1~ 2006-01-27 14:56:09.000000000 -0800
+++ ./expr.c 2006-01-27 15:46:14.000000000 -0800
@@ -6358,9 +6358,11 @@ expand_expr_addr_expr_1 (tree exp, rtx t
TREE_USED (exp) = 1;
}
+#if 0
if (modifier != EXPAND_INITIALIZER
&& modifier != EXPAND_CONST_ADDRESS)
result = force_operand (result, target);
+#endif
return result;
}
--- ./function.c.~1~ 2006-01-27 14:56:10.000000000 -0800
+++ ./function.c 2006-01-27 16:55:58.000000000 -0800
@@ -1455,6 +1455,18 @@ instantiate_virtual_regs_in_insn (rtx in
x = recog_data.operand[i];
switch (GET_CODE (x))
{
+ case PLUS:
+ {
+ bool changed = false;
+ rtx addr = x;
+
+ for_each_rtx (&addr, instantiate_virtual_regs_in_rtx, &changed);
+ x = addr;
+ if (!changed)
+ continue;
+ }
+ break;
+
case MEM:
{
rtx addr = XEXP (x, 0);
--- ./stmt.c.~1~ 2006-01-27 14:56:16.000000000 -0800
+++ ./stmt.c 2006-01-27 15:56:26.000000000 -0800
@@ -867,7 +867,7 @@ expand_asm_operands (tree string, tree o
type = TREE_TYPE (val);
op = expand_expr (val, NULL_RTX, VOIDmode,
(allows_mem && !allows_reg
- ? EXPAND_MEMORY : EXPAND_NORMAL));
+ ? EXPAND_MEMORY : EXPAND_SUM));
/* Never pass a CONCAT to an ASM. */
if (GET_CODE (op) == CONCAT)
--- ./tree-gimple.c.~1~ 2006-01-27 14:56:06.000000000 -0800
+++ ./tree-gimple.c 2006-01-27 15:41:37.000000000 -0800
@@ -386,6 +386,9 @@ is_gimple_asm_val (tree t)
if (TREE_CODE (t) == VAR_DECL && DECL_HARD_REGISTER (t))
return true;
+ if (TREE_CODE (t) == PLUS_EXPR)
+ return true;
+
return is_gimple_val (t);
}
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