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authorRichard Henderson <rth@twiddle.net>2012-10-10 09:02:40 -0700
committerBlue Swirl <blauwirbel@gmail.com>2012-10-13 10:39:53 +0000
commit7d458a7567ffde5b16d7a4b5e9f585434b2afc35 (patch)
tree380301dabff337b4d4cbb68dee451395ff2cd853 /tcg
parenta7a49843d70232e0f179e1da330355e5f03ab182 (diff)
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tcg-sparc: Fix setcond
The set of comparisons that can immediately use the carry are LTU/GEU, not LTU/LEU. Don't swap operands when we need a temp register; the register may already be in use from setcond2. Signed-off-by: Richard Henderson <rth@twiddle.net> Signed-off-by: Blue Swirl <blauwirbel@gmail.com>
Diffstat (limited to 'tcg')
-rw-r--r--tcg/sparc/tcg-target.c33
1 files changed, 19 insertions, 14 deletions
diff --git a/tcg/sparc/tcg-target.c b/tcg/sparc/tcg-target.c
index 3144044..31e8204 100644
--- a/tcg/sparc/tcg-target.c
+++ b/tcg/sparc/tcg-target.c
@@ -617,32 +617,37 @@ static void tcg_out_brcond2_i32(TCGContext *s, TCGCond cond,
static void tcg_out_setcond_i32(TCGContext *s, TCGCond cond, TCGArg ret,
TCGArg c1, TCGArg c2, int c2const)
{
- TCGArg t;
-
/* For 32-bit comparisons, we can play games with ADDX/SUBX. */
switch (cond) {
+ case TCG_COND_LTU:
+ case TCG_COND_GEU:
+ /* The result of the comparison is in the carry bit. */
+ break;
+
case TCG_COND_EQ:
case TCG_COND_NE:
+ /* For equality, we can transform to inequality vs zero. */
if (c2 != 0) {
tcg_out_arithc(s, ret, c1, c2, c2const, ARITH_XOR);
}
c1 = TCG_REG_G0, c2 = ret, c2const = 0;
- cond = (cond == TCG_COND_EQ ? TCG_COND_LEU : TCG_COND_LTU);
+ cond = (cond == TCG_COND_EQ ? TCG_COND_GEU : TCG_COND_LTU);
break;
case TCG_COND_GTU:
- case TCG_COND_GEU:
- if (c2const && c2 != 0) {
- tcg_out_movi_imm13(s, TCG_REG_T1, c2);
- c2 = TCG_REG_T1;
- }
- t = c1, c1 = c2, c2 = t, c2const = 0;
- cond = tcg_swap_cond(cond);
- break;
-
- case TCG_COND_LTU:
case TCG_COND_LEU:
- break;
+ /* If we don't need to load a constant into a register, we can
+ swap the operands on GTU/LEU. There's no benefit to loading
+ the constant into a temporary register. */
+ if (!c2const || c2 == 0) {
+ TCGArg t = c1;
+ c1 = c2;
+ c2 = t;
+ c2const = 0;
+ cond = tcg_swap_cond(cond);
+ break;
+ }
+ /* FALLTHRU */
default:
tcg_out_cmp(s, c1, c2, c2const);