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tcg-sparc: Fix setcond

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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>
This commit is contained in:
Richard Henderson 2012-10-10 09:02:40 -07:00 committed by Blue Swirl
parent a7a49843d7
commit 7d458a7567
1 changed files with 19 additions and 14 deletions
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33
tcg/sparc/tcg-target.c
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@ -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);