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| author | Segher Boessenkool <segher@kernel.crashing.org> | 2017-10-03 18:02:38 +0200 |
|---|---|---|
| committer | Segher Boessenkool <segher@gcc.gnu.org> | 2017-10-03 18:02:38 +0200 |
| commit | a8ccdfa8ea6fbdc78bdd5617427d7ba945cc83af (patch) | |
| tree | 50f8effb7cc092e35fba1cd02ad40548cf55e31b /gcc | |
| parent | 9c53f040cb3c3bc0b86f702af5bd73d904d6cf0f (diff) | |
| download | gcc-a8ccdfa8ea6fbdc78bdd5617427d7ba945cc83af.zip gcc-a8ccdfa8ea6fbdc78bdd5617427d7ba945cc83af.tar.gz gcc-a8ccdfa8ea6fbdc78bdd5617427d7ba945cc83af.tar.bz2 | |
simplify-rtx: Remove non-simplifying simplification (PR77729)
If we have (X&C1)|C2 simplify_binary_operation_1 makes C1 as small as
possible. This makes worse code in common cases like when the AND with
C1 is from a zero-extension. This patch fixes it by removing this
transformation (twice).
PR rtl-optimization/77729
* simplify-rtx.c (simplify_binary_operation_1): Delete the (X&C1)|C2
to (X&(C1&~C2))|C2 transformations.
From-SVN: r253384
Diffstat (limited to 'gcc')
| -rw-r--r-- | gcc/ChangeLog | 6 | ||||
| -rw-r--r-- | gcc/simplify-rtx.c | 25 |
2 files changed, 6 insertions, 25 deletions
diff --git a/gcc/ChangeLog b/gcc/ChangeLog index 33ae1be..9d43ae5 100644 --- a/gcc/ChangeLog +++ b/gcc/ChangeLog @@ -1,3 +1,9 @@ +2017-10-03 Segher Boessenkool <segher@kernel.crashing.org> + + PR rtl-optimization/77729 + * simplify-rtx.c (simplify_binary_operation_1): Delete the (X&C1)|C2 + to (X&(C1&~C2))|C2 transformations. + 2017-10-03 Martin Jambor <mjambor@suse.cz> PR tree-optimization/82363 diff --git a/gcc/simplify-rtx.c b/gcc/simplify-rtx.c index 1b960b9..3b6cf6f 100644 --- a/gcc/simplify-rtx.c +++ b/gcc/simplify-rtx.c @@ -2673,14 +2673,6 @@ simplify_binary_operation_1 (enum rtx_code code, machine_mode mode, /* If (C1|C2) == ~0 then (X&C1)|C2 becomes X|C2. */ if (((c1|c2) & mask) == mask) return simplify_gen_binary (IOR, mode, XEXP (op0, 0), op1); - - /* Minimize the number of bits set in C1, i.e. C1 := C1 & ~C2. */ - if (((c1 & ~c2) & mask) != (c1 & mask)) - { - tem = simplify_gen_binary (AND, mode, XEXP (op0, 0), - gen_int_mode (c1 & ~c2, mode)); - return simplify_gen_binary (IOR, mode, tem, op1); - } } /* Convert (A & B) | A to A. */ @@ -2736,23 +2728,6 @@ simplify_binary_operation_1 (enum rtx_code code, machine_mode mode, return gen_rtx_ROTATE (int_mode, XEXP (opright, 0), XEXP (SUBREG_REG (opleft), 1)); - /* If we have (ior (and (X C1) C2)), simplify this by making - C1 as small as possible if C1 actually changes. */ - if (CONST_INT_P (op1) - && (HWI_COMPUTABLE_MODE_P (mode) - || INTVAL (op1) > 0) - && GET_CODE (op0) == AND - && CONST_INT_P (XEXP (op0, 1)) - && CONST_INT_P (op1) - && (UINTVAL (XEXP (op0, 1)) & UINTVAL (op1)) != 0) - { - rtx tmp = simplify_gen_binary (AND, mode, XEXP (op0, 0), - gen_int_mode (UINTVAL (XEXP (op0, 1)) - & ~UINTVAL (op1), - mode)); - return simplify_gen_binary (IOR, mode, tmp, op1); - } - /* If OP0 is (ashiftrt (plus ...) C), it might actually be a (sign_extend (plus ...)). Then check if OP1 is a CONST_INT and the PLUS does not affect any of the bits in OP1: then we can do |