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| author | Geoffrey Keating <geoffk@apple.com> | 2002-12-05 01:05:13 +0000 |
|---|---|---|
| committer | Geoffrey Keating <geoffk@gcc.gnu.org> | 2002-12-05 01:05:13 +0000 |
| commit | 16823694d5a03199161bfb60157a9a6e3a2ee697 (patch) | |
| tree | a75fcb2170c99b7b343e9abad85d48152fdd43c2 /gcc/combine.c | |
| parent | 76508852a0241db33b2512c0b460cdf06f7e0ce5 (diff) | |
| download | gcc-16823694d5a03199161bfb60157a9a6e3a2ee697.zip gcc-16823694d5a03199161bfb60157a9a6e3a2ee697.tar.gz gcc-16823694d5a03199161bfb60157a9a6e3a2ee697.tar.bz2 | |
Index: gcc/ChangeLog
2002-12-02 Geoffrey Keating <geoffk@apple.com>
* combine.c (combine_simplify_rtx): Add new canonicalizations.
* doc/md.texi (Insn Canonicalizations): Document new
canonicalizations for multiply/add combinations.
* config/rs6000/rs6000.md: Add and modify floating add/multiply
patterns to ensure they're used whenever they can be.
Index: gcc/testsuite/ChangeLog
2002-12-02 Geoffrey Keating <geoffk@apple.com>
* gcc.dg/ppc-fmadd-1.c: New file.
* gcc.dg/ppc-fmadd-2.c: New file.
* gcc.dg/ppc-fmadd-3.c: New file.
From-SVN: r59841
Diffstat (limited to 'gcc/combine.c')
| -rw-r--r-- | gcc/combine.c | 57 |
1 files changed, 57 insertions, 0 deletions
diff --git a/gcc/combine.c b/gcc/combine.c index a0214d1..4d24807 100644 --- a/gcc/combine.c +++ b/gcc/combine.c @@ -4029,6 +4029,24 @@ combine_simplify_rtx (x, op0_mode, last, in_dest) return gen_binary (MINUS, mode, XEXP (XEXP (x, 0), 1), XEXP (XEXP (x, 0), 0)); + /* (neg (plus A B)) is canonicalized to (minus (neg A) B). */ + if (GET_CODE (XEXP (x, 0)) == PLUS + && !HONOR_SIGNED_ZEROS (mode) + && !HONOR_SIGN_DEPENDENT_ROUNDING (mode)) + { + temp = simplify_gen_unary (NEG, mode, XEXP (XEXP (x, 0), 0), mode); + temp = combine_simplify_rtx (temp, mode, last, in_dest); + return gen_binary (MINUS, mode, temp, XEXP (XEXP (x, 0), 1)); + } + + /* (neg (mult A B)) becomes (mult (neg A) B). + This works even for floating-point values. */ + if (GET_CODE (XEXP (x, 0)) == MULT) + { + temp = simplify_gen_unary (NEG, mode, XEXP (XEXP (x, 0), 0), mode); + return gen_binary (MULT, mode, temp, XEXP (XEXP (x, 0), 1)); + } + /* (neg (xor A 1)) is (plus A -1) if A is known to be either 0 or 1. */ if (GET_CODE (XEXP (x, 0)) == XOR && XEXP (XEXP (x, 0), 1) == const1_rtx && nonzero_bits (XEXP (XEXP (x, 0), 0), mode) == 1) @@ -4217,6 +4235,19 @@ combine_simplify_rtx (x, op0_mode, last, in_dest) #endif case PLUS: + /* Canonicalize (plus (mult (neg B) C) A) to (minus A (mult B C)). + */ + if (GET_CODE (XEXP (x, 0)) == MULT + && GET_CODE (XEXP (XEXP (x, 0), 0)) == NEG) + { + rtx in1, in2; + + in1 = XEXP (XEXP (XEXP (x, 0), 0), 0); + in2 = XEXP (XEXP (x, 0), 1); + return gen_binary (MINUS, mode, XEXP (x, 1), + gen_binary (MULT, mode, in1, in2)); + } + /* If we have (plus (plus (A const) B)), associate it so that CONST is outermost. That's because that's the way indexed addresses are supposed to appear. This code used to check many more cases, but @@ -4323,6 +4354,32 @@ combine_simplify_rtx (x, op0_mode, last, in_dest) return simplify_and_const_int (NULL_RTX, mode, XEXP (x, 0), -INTVAL (XEXP (XEXP (x, 1), 1)) - 1); + /* Canonicalize (minus A (mult (neg B) C)) to (plus (mult B C) A). + */ + if (GET_CODE (XEXP (x, 1)) == MULT + && GET_CODE (XEXP (XEXP (x, 1), 0)) == NEG) + { + rtx in1, in2; + + in1 = XEXP (XEXP (XEXP (x, 1), 0), 0); + in2 = XEXP (XEXP (x, 1), 1); + return gen_binary (PLUS, mode, gen_binary (MULT, mode, in1, in2), + XEXP (x, 0)); + } + + /* Canonicalize (minus (neg A) (mult B C)) to + (minus (mult (neg B) C) A). */ + if (GET_CODE (XEXP (x, 1)) == MULT + && GET_CODE (XEXP (x, 0)) == NEG) + { + rtx in1, in2; + + in1 = simplify_gen_unary (NEG, mode, XEXP (XEXP (x, 1), 0), mode); + in2 = XEXP (XEXP (x, 1), 1); + return gen_binary (MINUS, mode, gen_binary (MULT, mode, in1, in2), + XEXP (XEXP (x, 0), 0)); + } + /* Canonicalize (minus A (plus B C)) to (minus (minus A B) C) for integers. */ if (GET_CODE (XEXP (x, 1)) == PLUS && INTEGRAL_MODE_P (mode)) |