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| author | Steven Bosscher <stevenb@suse.de> | 2005-12-16 22:19:09 +0000 |
|---|---|---|
| committer | Steven Bosscher <steven@gcc.gnu.org> | 2005-12-16 22:19:09 +0000 |
| commit | ebd8b60da18203d983ab65a5f3d20c70bf8f6348 (patch) | |
| tree | 27cbf67bba2b87ad3d3700394b9e945821f96440 | |
| parent | f3a1a6532fbce3ce51c71b07d5141c1f5f48c176 (diff) | |
| download | gcc-ebd8b60da18203d983ab65a5f3d20c70bf8f6348.zip gcc-ebd8b60da18203d983ab65a5f3d20c70bf8f6348.tar.gz gcc-ebd8b60da18203d983ab65a5f3d20c70bf8f6348.tar.bz2 | |
re PR rtl-optimization/23837 (Wrong code with REG_NO_CONFLICT notes (caused by combine))
PR rtl-optimization/23837
* optabs.c (expand_binop): For a multi-word rotate, never emit
a REG_NO_CONFLICT block.
From-SVN: r108690
| -rw-r--r-- | gcc/ChangeLog | 6 | ||||
| -rw-r--r-- | gcc/optabs.c | 22 |
2 files changed, 13 insertions, 15 deletions
diff --git a/gcc/ChangeLog b/gcc/ChangeLog index fd9c62c..4f36c02 100644 --- a/gcc/ChangeLog +++ b/gcc/ChangeLog @@ -1,3 +1,9 @@ +2005-12-16 Steven Bosscher <stevenb@suse.de> + + PR rtl-optimization/23837 + * optabs.c (expand_binop): For a multi-word rotate, never emit + a REG_NO_CONFLICT block. + 2005-12-16 John David Anglin <dave.anglin@nrc-cnrc.gc.ca> PR middle-end/25457 diff --git a/gcc/optabs.c b/gcc/optabs.c index a72028e..45bfbbd 100644 --- a/gcc/optabs.c +++ b/gcc/optabs.c @@ -1420,7 +1420,7 @@ expand_binop (enum machine_mode mode, optab binoptab, rtx op0, rtx op1, && ashl_optab->handlers[(int) word_mode].insn_code != CODE_FOR_nothing && lshr_optab->handlers[(int) word_mode].insn_code != CODE_FOR_nothing) { - rtx insns, equiv_value; + rtx insns; rtx into_target, outof_target; rtx into_input, outof_input; rtx inter; @@ -1520,20 +1520,12 @@ expand_binop (enum machine_mode mode, optab binoptab, rtx op0, rtx op1, if (inter != 0) { - if (binoptab->code != UNKNOWN) - equiv_value = gen_rtx_fmt_ee (binoptab->code, mode, op0, op1); - else - equiv_value = 0; - - /* We can't make this a no conflict block if this is a word swap, - because the word swap case fails if the input and output values - are in the same register. */ - if (shift_count != BITS_PER_WORD) - emit_no_conflict_block (insns, target, op0, op1, equiv_value); - else - emit_insn (insns); - - + /* One may be tempted to wrap the insns in a REG_NO_CONFLICT + block to help the register allocator a bit. But a multi-word + rotate will need all the input bits when setting the output + bits, so there clearly is a conflict between the input and + output registers. So we can't use a no-conflict block here. */ + emit_insn (insns); return target; } } |