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| author | Richard Kenner <kenner@gcc.gnu.org> | 1994-01-23 07:00:29 -0500 |
|---|---|---|
| committer | Richard Kenner <kenner@gcc.gnu.org> | 1994-01-23 07:00:29 -0500 |
| commit | ad25ba1779f5e1a0e2a640e12dda3f6c7a53a163 (patch) | |
| tree | c80f3964fca696ddf817b152ee5f48f23cc293d7 /gcc | |
| parent | 2f607b946a7052254062f863a36ba1e7b6de80d1 (diff) | |
| download | gcc-ad25ba1779f5e1a0e2a640e12dda3f6c7a53a163.zip gcc-ad25ba1779f5e1a0e2a640e12dda3f6c7a53a163.tar.gz gcc-ad25ba1779f5e1a0e2a640e12dda3f6c7a53a163.tar.bz2 | |
(simplify_comparison): Can remove NOT on both operands if we swap
comparison code.
From-SVN: r6410
Diffstat (limited to 'gcc')
| -rw-r--r-- | gcc/combine.c | 15 |
1 files changed, 8 insertions, 7 deletions
diff --git a/gcc/combine.c b/gcc/combine.c index d699367..1737e6e 100644 --- a/gcc/combine.c +++ b/gcc/combine.c @@ -8429,7 +8429,7 @@ simplify_comparison (code, pop0, pop1) && GET_CODE (XEXP (XEXP (op0, 0), 0)) == SUBREG && GET_CODE (XEXP (XEXP (op1, 0), 0)) == SUBREG && (GET_MODE (SUBREG_REG (XEXP (XEXP (op0, 0), 0))) - == GET_MODE (SUBREG_REG (XEXP (XEXP (op0, 0), 0)))) + == GET_MODE (SUBREG_REG (XEXP (XEXP (op1, 0), 0)))) && GET_CODE (XEXP (op0, 1)) == CONST_INT && GET_CODE (XEXP (op1, 1)) == CONST_INT && GET_CODE (XEXP (XEXP (op0, 0), 1)) == CONST_INT @@ -8517,12 +8517,13 @@ simplify_comparison (code, pop0, pop1) code = unsigned_condition (code); } - /* If both operands are NOT or both are NEG, we can strip off the - outer operation if this is just an equality comparison. */ - else if ((code == EQ || code == NE) - && ((GET_CODE (op0) == NOT && GET_CODE (op1) == NOT) - || (GET_CODE (op0) == NEG && GET_CODE (op1) == NEG))) - op0 = XEXP (op0, 0), op1 = XEXP (op1, 0); + /* If both operands are NOT, we can strip off the outer operation + and adjust the comparison code for swapped operands; similarly for + NEG, except that this must be an equality comparison. */ + else if ((GET_CODE (op0) == NOT && GET_CODE (op1) == NOT) + || (GET_CODE (op0) == NEG && GET_CODE (op1) == NEG + && (code == EQ || code == NE))) + op0 = XEXP (op0, 0), op1 = XEXP (op1, 0), code = swap_condition (code); else break; |