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| author | Jan Beulich <jbeulich@novell.com> | 2004-07-08 06:08:52 +0000 |
|---|---|---|
| committer | Richard Henderson <rth@gcc.gnu.org> | 2004-07-07 23:08:52 -0700 |
| commit | 884815aa85fb661f34e3ea02c2a5b5aa02622ded (patch) | |
| tree | a82a020cc231752174fc7f29a3b995cabb06c7a0 /gcc/expmed.c | |
| parent | ff15c351eda434655cde7e6153b1a27db404a86d (diff) | |
| download | gcc-884815aa85fb661f34e3ea02c2a5b5aa02622ded.zip gcc-884815aa85fb661f34e3ea02c2a5b5aa02622ded.tar.gz gcc-884815aa85fb661f34e3ea02c2a5b5aa02622ded.tar.bz2 | |
expmed.c (emit_store_flag): Also special-case double-word (in-)equality comparison against -1.
* expmed.c (emit_store_flag): Also special-case double-word
(in-)equality comparison against -1.
From-SVN: r84268
Diffstat (limited to 'gcc/expmed.c')
| -rw-r--r-- | gcc/expmed.c | 18 |
1 files changed, 10 insertions, 8 deletions
diff --git a/gcc/expmed.c b/gcc/expmed.c index 6ee2913..ba3c9a6 100644 --- a/gcc/expmed.c +++ b/gcc/expmed.c @@ -4602,27 +4602,29 @@ emit_store_flag (rtx target, enum rtx_code code, rtx op0, rtx op1, break; } - /* If we are comparing a double-word integer with zero, we can convert - the comparison into one involving a single word. */ + /* If we are comparing a double-word integer with zero or -1, we can + convert the comparison into one involving a single word. */ if (GET_MODE_BITSIZE (mode) == BITS_PER_WORD * 2 && GET_MODE_CLASS (mode) == MODE_INT - && op1 == const0_rtx && (!MEM_P (op0) || ! MEM_VOLATILE_P (op0))) { - if (code == EQ || code == NE) + if ((code == EQ || code == NE) + && (op1 == const0_rtx || op1 == constm1_rtx)) { rtx op00, op01, op0both; - /* Do a logical OR of the two words and compare the result. */ + /* Do a logical OR or AND of the two words and compare the result. */ op00 = simplify_gen_subreg (word_mode, op0, mode, 0); op01 = simplify_gen_subreg (word_mode, op0, mode, UNITS_PER_WORD); - op0both = expand_binop (word_mode, ior_optab, op00, op01, - NULL_RTX, unsignedp, OPTAB_DIRECT); + op0both = expand_binop (word_mode, + op1 == const0_rtx ? ior_optab : and_optab, + op00, op01, NULL_RTX, unsignedp, OPTAB_DIRECT); + if (op0both != 0) return emit_store_flag (target, code, op0both, op1, word_mode, unsignedp, normalizep); } - else if (code == LT || code == GE) + else if ((code == LT || code == GE) && op1 == const0_rtx) { rtx op0h; |