>From b4e4cff8815d171242e4df167cd8eef87cb5615d Mon Sep 17 00:00:00 2001
From: Kael Andrew Alonzo Franco <[email protected]>
Date: Mon, 3 Aug 2026 16:19:49 -0400
Subject: [PATCH] match: Combine several patterns into fors.
This reduce genmatch's outputted C++ code.
Bootstrapped and regtested on x86_64-pc-linux-gnu.
gcc/ChangeLog:
* match.pd: Combine several patterns into fors.
Signed-off-by: Kael Andrew Franco <[email protected]>
---
gcc/match.pd | 64 +++++++++++++++++++++++-----------------------------
1 file changed, 28 insertions(+), 36 deletions(-)
diff --git a/gcc/match.pd b/gcc/match.pd
index 293650760e2..6763ab412c0 100644
--- a/gcc/match.pd
+++ b/gcc/match.pd
@@ -1346,8 +1346,8 @@ DEFINE_INT_AND_FLOAT_ROUND_FN (RINT)
(mult:c @0 (vec_cond (ne @0 integer_zerop) integer_zerop@2 @1))
@2)
-/* Shifts by precision or greater result in zero. */
(for shift (lshift rshift)
+ /* Shifts by precision or greater result in zero. */
(simplify
(shift @0 uniform_integer_cst_p@1)
(if ((GIMPLE || !sanitize_flags_p (SANITIZE_SHIFT_EXPONENT))
@@ -1358,10 +1358,18 @@ DEFINE_INT_AND_FLOAT_ROUND_FN (RINT)
/* Use a signed compare to leave negative shift counts alone. */
&& wi::ges_p (wi::to_wide (uniform_integer_cst_p (@1)),
element_precision (type)))
- { build_zero_cst (type); })))
+ { build_zero_cst (type); }))
+ /* Shifts by constants distribute over several binary operations:
+ (X (<<, >>) C) & (Y (<<, >>) C) -> (X & Y) (<<, >>) C.
+ (X (<<, >>) C) | (Y (<<, >>) C) -> (X | Y) (<<, >>) C.
+ (X (<<, >>) C) ^ (Y (<<, >>) C) -> (X ^ Y) (<<, >>) C. */
+ (for op (bit_and bit_ior bit_xor)
+ (simplify
+ (op (shift:s @0 @1) (shift:s @2 @1))
+ (if (INTEGRAL_TYPE_P (type))
+ (shift (op @0 @2) @1)))))
-/* Shifts by constants distribute over several binary operations,
- hence (X << C) + (Y << C) can be simplified to (X + Y) << C. */
+/* (X << C) (+,-) (Y << C) -> (X (+,-) Y) << C. */
(for op (plus minus)
(simplify
(op (lshift:s @0 @1) (lshift:s @2 @1))
@@ -1370,16 +1378,6 @@ DEFINE_INT_AND_FLOAT_ROUND_FN (RINT)
&& !TYPE_SATURATING (type))
(lshift (op @0 @2) @1))))
-(for op (bit_and bit_ior bit_xor)
- (simplify
- (op (lshift:s @0 @1) (lshift:s @2 @1))
- (if (INTEGRAL_TYPE_P (type))
- (lshift (op @0 @2) @1)))
- (simplify
- (op (rshift:s @0 @1) (rshift:s @2 @1))
- (if (INTEGRAL_TYPE_P (type))
- (rshift (op @0 @2) @1))))
-
/* (y << x) == x -> false and (y << x) != x -> true when y != 0. */
(for cmp (eq ne)
(simplify
@@ -1941,27 +1939,29 @@ DEFINE_INT_AND_FLOAT_ROUND_FN (RINT)
(bit_xor:c (bit_ior:c @0 @1) (bit_ior:c @0 (bit_not @1)))
(bit_not @0))
-/* (x & y) | ~(x | y) -> ~(x ^ y)
- (x ^ y) | ~(x | y) -> ~(x & y) */
-(for lop (bit_and bit_xor)
- res (bit_xor bit_and)
+(for op (bit_and bit_xor)
+ rop (bit_xor bit_and)
+ /* (x & y) | ~(x | y) -> ~(x ^ y)
+ (x ^ y) | ~(x | y) -> ~(x & y) */
+ (simplify
+ (bit_ior:c (op:s @0 @1) (bit_not:s (bit_ior:s @0 @1)))
+ (bit_not (rop @0 @1)))
+ /* (x & y) ^ (x | y) -> x ^ y
+ (x ^ y) ^ (x | y) -> x & y */
+ (simplify
+ (bit_xor:c (op @0 @1) (bit_ior @0 @1))
+ (rop @0 @1))
+ /* (x | y) - (x & y) -> x ^ y
+ (x | y) - (x ^ y) -> x & y */
(simplify
- (bit_ior:c (lop:s @0 @1) (bit_not:s (bit_ior:s @0 @1)))
- (bit_not (res @0 @1))))
+ (minus (bit_ior @0 @1) (op @0 @1))
+ (rop @0 @1)))
/* (~x | y) ^ (x ^ y) -> x | ~y */
(simplify
(bit_xor:c (bit_ior:cs (bit_not @0) @1) (bit_xor:s @0 @1))
(bit_ior @0 (bit_not @1)))
-/* (x & y) ^ (x | y) -> x ^ y
- (x ^ y) ^ (x | y) -> x & y */
-(for lop (bit_and bit_xor)
- res (bit_xor bit_and)
- (simplify
- (bit_xor:c (lop @0 @1) (bit_ior @0 @1))
- (res @0 @1)))
-
/* (x & y) + (x ^ y) -> x | y */
/* (x & y) | (x ^ y) -> x | y */
/* (x & y) ^ (x ^ y) -> x | y */
@@ -1990,14 +1990,6 @@ DEFINE_INT_AND_FLOAT_ROUND_FN (RINT)
(minus (bit_ior:cs @0 @1) @1)
(bit_and @0 (bit_not @1)))
-/* (x | y) - (x ^ y) -> x & y
- (x | y) - (x & y) -> x ^ y */
-(for rop (bit_xor bit_and)
- res (bit_and bit_xor)
- (simplify
- (minus (bit_ior @0 @1) (rop @0 @1))
- (res @0 @1)))
-
/* (x | y) & ~(x & y) -> x ^ y */
(simplify
(bit_and:c (bit_ior @0 @1) (bit_not (bit_and @0 @1)))
--
2.55.0
