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| author | Richard Henderson <rth@redhat.com> | 2001-07-23 14:16:02 -0700 |
|---|---|---|
| committer | Richard Henderson <rth@gcc.gnu.org> | 2001-07-23 14:16:02 -0700 |
| commit | c50e5bc0abd1531bdc12772fe236b1053001a22a (patch) | |
| tree | b37259266f119c03012626be17bb5bf989e23210 /gcc | |
| parent | 9099cc4f790939fe710dc400cef829cf8c0894ff (diff) | |
| download | gcc-c50e5bc0abd1531bdc12772fe236b1053001a22a.zip gcc-c50e5bc0abd1531bdc12772fe236b1053001a22a.tar.gz gcc-c50e5bc0abd1531bdc12772fe236b1053001a22a.tar.bz2 | |
i386.c (ix86_expand_setcc): Don't use method 0 before CSE.
* config/i386/i386.c (ix86_expand_setcc): Don't use method 0
before CSE.
* config/i386/i386.md: New setcc+movzbl peephole2.
From-SVN: r44279
Diffstat (limited to 'gcc')
| -rw-r--r-- | gcc/ChangeLog | 6 | ||||
| -rw-r--r-- | gcc/config/i386/i386.c | 7 | ||||
| -rw-r--r-- | gcc/config/i386/i386.md | 19 |
3 files changed, 30 insertions, 2 deletions
diff --git a/gcc/ChangeLog b/gcc/ChangeLog index 697b11a..e2437a2 100644 --- a/gcc/ChangeLog +++ b/gcc/ChangeLog @@ -1,3 +1,9 @@ +2001-07-23 Richard Henderson <rth@redhat.com> + + * config/i386/i386.c (ix86_expand_setcc): Don't use method 0 + before CSE. + * config/i386/i386.md: New setcc+movzbl peephole2. + 2001-07-23 Neil Booth <neil@cat.daikokuya.demon.co.uk> * objc/Make-lang.in (objc-act.o): Depend on debug.h. diff --git a/gcc/config/i386/i386.c b/gcc/config/i386/i386.c index 821daa6..725a984 100644 --- a/gcc/config/i386/i386.c +++ b/gcc/config/i386/i386.c @@ -6357,9 +6357,12 @@ ix86_expand_setcc (code, dest) emit subreg setcc, zero extend. 2 -- destination is in QImode: emit setcc only. - */ - type = 0; + We don't use mode 0 early in compilation because it confuses CSE. + There are peepholes to turn mode 1 into mode 0 if things work out + nicely after reload. */ + + type = cse_not_expected ? 0 : 1; if (GET_MODE (dest) == QImode) type = 2; diff --git a/gcc/config/i386/i386.md b/gcc/config/i386/i386.md index d2ff08b..7f84549 100644 --- a/gcc/config/i386/i386.md +++ b/gcc/config/i386/i386.md @@ -13133,6 +13133,25 @@ (match_dup 0) (pc)))] "") + +;; Convert setcc + movzbl to xor + setcc if operands don't overlap. + +(define_peephole2 + [(set (reg 17) (match_operand 0 "" "")) + (set (match_operand:QI 1 "register_operand" "") + (match_operator:QI 2 "ix86_comparison_operator" + [(reg 17) (const_int 0)])) + (set (match_operand 3 "q_regs_operand" "") + (zero_extend (match_dup 1)))] + "peep2_reg_dead_p (3, operands[1]) + && ! reg_overlap_mentioned_p (operands[3], operands[0])" + [(parallel [(set (match_dup 3) (const_int 0)) + (clobber (reg:CC 17))]) + (set (match_dup 4) (match_dup 0)) + (set (strict_low_part (match_dup 5)) + (match_dup 2))] + "operands[4] = gen_rtx_REG (GET_MODE (operands[0]), 17); + operands[5] = gen_rtx_REG (QImode, REGNO (operands[3]));") ;; Call instructions. |