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 <r...@twiddle.net>
---
tcg/sparc/tcg-target.c | 33 +++++++++++++++++++--------------
1 file changed, 19 insertions(+), 14 deletions(-)
diff --git a/tcg/sparc/tcg-target.c b/tcg/sparc/tcg-target.c
index e55b792..c3e15b9 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);
--
1.7.11.4
