> I suppose the idea is that -abs(x) might be easier to optimize with other > patterns (consider a - copysign(x,...), optimizing to a + abs(x)). > > For abs vs copysign it's a canonicalization, but (negate (abs @0)) is less > canonical than copysign. > > > Should I try removing this? > > I'd say yes (and put the reverse canonicalization next to this pattern). >
This patch transforms fneg (fabs (x)) into copysign (x, -1) which is more
canonical and allows a target to expand this sequence efficiently. Such
sequences are common in scientific code working with gradients.
various optimizations in match.pd only happened on COPYSIGN but not COPYSIGN_ALL
which means they exclude IFN_COPYSIGN. COPYSIGN however is restricted to only
the C99 builtins and so doesn't work for vectors.
The patch expands these optimizations to work on COPYSIGN_ALL.
There is an existing canonicalization of copysign (x, -1) to fneg (fabs (x))
which I remove since this is a less efficient form. The testsuite is also
updated in light of this.
Bootstrapped Regtested on aarch64-none-linux-gnu and no issues.
Ok for master?
Thanks,
Tamar
gcc/ChangeLog:
PR tree-optimization/109154
* match.pd: Add new neg+abs rule, remove inverse copysign rule and
expand existing copysign optimizations.
gcc/testsuite/ChangeLog:
PR tree-optimization/109154
* gcc.dg/fold-copysign-1.c: Updated.
* gcc.dg/pr55152-2.c: Updated.
* gcc.dg/tree-ssa/abs-4.c: Updated.
* gcc.dg/tree-ssa/backprop-6.c: Updated.
* gcc.dg/tree-ssa/copy-sign-2.c: Updated.
* gcc.dg/tree-ssa/mult-abs-2.c: Updated.
* gcc.target/aarch64/fneg-abs_1.c: New test.
* gcc.target/aarch64/fneg-abs_2.c: New test.
* gcc.target/aarch64/fneg-abs_3.c: New test.
* gcc.target/aarch64/fneg-abs_4.c: New test.
* gcc.target/aarch64/sve/fneg-abs_1.c: New test.
* gcc.target/aarch64/sve/fneg-abs_2.c: New test.
* gcc.target/aarch64/sve/fneg-abs_3.c: New test.
* gcc.target/aarch64/sve/fneg-abs_4.c: New test.
--- inline copy of patch ---
diff --git a/gcc/match.pd b/gcc/match.pd
index
4bdd83e6e061b16dbdb2845b9398fcfb8a6c9739..bd6599d36021e119f51a4928354f580ffe82c6e2
100644
--- a/gcc/match.pd
+++ b/gcc/match.pd
@@ -1074,45 +1074,43 @@ DEFINE_INT_AND_FLOAT_ROUND_FN (RINT)
/* cos(copysign(x, y)) -> cos(x). Similarly for cosh. */
(for coss (COS COSH)
- copysigns (COPYSIGN)
- (simplify
- (coss (copysigns @0 @1))
- (coss @0)))
+ (for copysigns (COPYSIGN_ALL)
+ (simplify
+ (coss (copysigns @0 @1))
+ (coss @0))))
/* pow(copysign(x, y), z) -> pow(x, z) if z is an even integer. */
(for pows (POW)
- copysigns (COPYSIGN)
- (simplify
- (pows (copysigns @0 @2) REAL_CST@1)
- (with { HOST_WIDE_INT n; }
- (if (real_isinteger (&TREE_REAL_CST (@1), &n) && (n & 1) == 0)
- (pows @0 @1)))))
+ (for copysigns (COPYSIGN_ALL)
+ (simplify
+ (pows (copysigns @0 @2) REAL_CST@1)
+ (with { HOST_WIDE_INT n; }
+ (if (real_isinteger (&TREE_REAL_CST (@1), &n) && (n & 1) == 0)
+ (pows @0 @1))))))
/* Likewise for powi. */
(for pows (POWI)
- copysigns (COPYSIGN)
- (simplify
- (pows (copysigns @0 @2) INTEGER_CST@1)
- (if ((wi::to_wide (@1) & 1) == 0)
- (pows @0 @1))))
+ (for copysigns (COPYSIGN_ALL)
+ (simplify
+ (pows (copysigns @0 @2) INTEGER_CST@1)
+ (if ((wi::to_wide (@1) & 1) == 0)
+ (pows @0 @1)))))
(for hypots (HYPOT)
- copysigns (COPYSIGN)
- /* hypot(copysign(x, y), z) -> hypot(x, z). */
- (simplify
- (hypots (copysigns @0 @1) @2)
- (hypots @0 @2))
- /* hypot(x, copysign(y, z)) -> hypot(x, y). */
- (simplify
- (hypots @0 (copysigns @1 @2))
- (hypots @0 @1)))
+ (for copysigns (COPYSIGN)
+ /* hypot(copysign(x, y), z) -> hypot(x, z). */
+ (simplify
+ (hypots (copysigns @0 @1) @2)
+ (hypots @0 @2))
+ /* hypot(x, copysign(y, z)) -> hypot(x, y). */
+ (simplify
+ (hypots @0 (copysigns @1 @2))
+ (hypots @0 @1))))
-/* copysign(x, CST) -> [-]abs (x). */
-(for copysigns (COPYSIGN_ALL)
- (simplify
- (copysigns @0 REAL_CST@1)
- (if (REAL_VALUE_NEGATIVE (TREE_REAL_CST (@1)))
- (negate (abs @0))
- (abs @0))))
+/* Transform fneg (fabs (X)) -> copysign (X, -1). */
+
+(simplify
+ (negate (abs @0))
+ (IFN_COPYSIGN @0 { build_minus_one_cst (type); }))
/* copysign(copysign(x, y), z) -> copysign(x, z). */
(for copysigns (COPYSIGN_ALL)
diff --git a/gcc/testsuite/gcc.dg/fold-copysign-1.c
b/gcc/testsuite/gcc.dg/fold-copysign-1.c
index
f17d65c24ee4dca9867827d040fe0a404c515e7b..f9cafd14ab05f5e8ab2f6f68e62801d21c2df6a6
100644
--- a/gcc/testsuite/gcc.dg/fold-copysign-1.c
+++ b/gcc/testsuite/gcc.dg/fold-copysign-1.c
@@ -12,5 +12,5 @@ double bar (double x)
return __builtin_copysign (x, minuszero);
}
-/* { dg-final { scan-tree-dump-times "= -" 1 "cddce1" } } */
-/* { dg-final { scan-tree-dump-times "= ABS_EXPR" 2 "cddce1" } } */
+/* { dg-final { scan-tree-dump-times "__builtin_copysign" 1 "cddce1" } } */
+/* { dg-final { scan-tree-dump-times "= ABS_EXPR" 1 "cddce1" } } */
diff --git a/gcc/testsuite/gcc.dg/pr55152-2.c b/gcc/testsuite/gcc.dg/pr55152-2.c
index
54db0f2062da105a829d6690ac8ed9891fe2b588..605f202ed6bc7aa8fe921457b02ff0b88cc63ce6
100644
--- a/gcc/testsuite/gcc.dg/pr55152-2.c
+++ b/gcc/testsuite/gcc.dg/pr55152-2.c
@@ -10,4 +10,5 @@ int f(int a)
return (a<-a)?a:-a;
}
-/* { dg-final { scan-tree-dump-times "ABS_EXPR" 2 "optimized" } } */
+/* { dg-final { scan-tree-dump-times "\.COPYSIGN" 1 "optimized" } } */
+/* { dg-final { scan-tree-dump-times "ABS_EXPR" 1 "optimized" } } */
diff --git a/gcc/testsuite/gcc.dg/tree-ssa/abs-4.c
b/gcc/testsuite/gcc.dg/tree-ssa/abs-4.c
index
6197519faf7b55aed7bc162cd0a14dd2145210ca..e1b825f37f69ac3c4666b3a52d733368805ad31d
100644
--- a/gcc/testsuite/gcc.dg/tree-ssa/abs-4.c
+++ b/gcc/testsuite/gcc.dg/tree-ssa/abs-4.c
@@ -9,5 +9,6 @@ long double abs_ld(long double x) { return __builtin_signbit(x)
? x : -x; }
/* __builtin_signbit(x) ? x : -x. Should be convert into - ABS_EXP<x> */
/* { dg-final { scan-tree-dump-not "signbit" "optimized"} } */
-/* { dg-final { scan-tree-dump-times "= ABS_EXPR" 3 "optimized"} } */
-/* { dg-final { scan-tree-dump-times "= -" 3 "optimized"} } */
+/* { dg-final { scan-tree-dump-times "= ABS_EXPR" 1 "optimized"} } */
+/* { dg-final { scan-tree-dump-times "= -" 1 "optimized"} } */
+/* { dg-final { scan-tree-dump-times "= \.COPYSIGN" 2 "optimized"} } */
diff --git a/gcc/testsuite/gcc.dg/tree-ssa/backprop-6.c
b/gcc/testsuite/gcc.dg/tree-ssa/backprop-6.c
index
31f05716f1498dc709cac95fa20fb5796642c77e..c3a138642d6ff7be984e91fa1343cb2718db7ae1
100644
--- a/gcc/testsuite/gcc.dg/tree-ssa/backprop-6.c
+++ b/gcc/testsuite/gcc.dg/tree-ssa/backprop-6.c
@@ -26,5 +26,6 @@ TEST_FUNCTION (float, f)
TEST_FUNCTION (double, )
TEST_FUNCTION (long double, l)
-/* { dg-final { scan-tree-dump-times {Deleting[^\n]* = -} 6 "backprop" } } */
-/* { dg-final { scan-tree-dump-times {Deleting[^\n]* = ABS_EXPR <} 3
"backprop" } } */
+/* { dg-final { scan-tree-dump-times {Deleting[^\n]* = -} 4 "backprop" } } */
+/* { dg-final { scan-tree-dump-times {Deleting[^\n]* = \.COPYSIGN} 2
"backprop" } } */
+/* { dg-final { scan-tree-dump-times {Deleting[^\n]* = ABS_EXPR <} 1
"backprop" } } */
diff --git a/gcc/testsuite/gcc.dg/tree-ssa/copy-sign-2.c
b/gcc/testsuite/gcc.dg/tree-ssa/copy-sign-2.c
index
de52c5f7c8062958353d91f5031193defc9f3f91..e5d565c4b9832c00106588ef411fbd8c292a5cad
100644
--- a/gcc/testsuite/gcc.dg/tree-ssa/copy-sign-2.c
+++ b/gcc/testsuite/gcc.dg/tree-ssa/copy-sign-2.c
@@ -10,4 +10,5 @@ float f1(float x)
float t = __builtin_copysignf (1.0f, -x);
return x * t;
}
-/* { dg-final { scan-tree-dump-times "ABS" 2 "optimized"} } */
+/* { dg-final { scan-tree-dump-times "ABS" 1 "optimized"} } */
+/* { dg-final { scan-tree-dump-times ".COPYSIGN" 1 "optimized"} } */
diff --git a/gcc/testsuite/gcc.dg/tree-ssa/mult-abs-2.c
b/gcc/testsuite/gcc.dg/tree-ssa/mult-abs-2.c
index
a41f1baf25669a4fd301a586a49ba5e3c5b966ab..a22896b21c8b5a4d5d8e28bd8ae0db896e63ade0
100644
--- a/gcc/testsuite/gcc.dg/tree-ssa/mult-abs-2.c
+++ b/gcc/testsuite/gcc.dg/tree-ssa/mult-abs-2.c
@@ -34,4 +34,5 @@ float i1(float x)
{
return x * (x <= 0.f ? 1.f : -1.f);
}
-/* { dg-final { scan-tree-dump-times "ABS" 8 "gimple"} } */
+/* { dg-final { scan-tree-dump-times "ABS" 4 "gimple"} } */
+/* { dg-final { scan-tree-dump-times "\.COPYSIGN" 4 "gimple"} } */
diff --git a/gcc/testsuite/gcc.target/aarch64/fneg-abs_1.c
b/gcc/testsuite/gcc.target/aarch64/fneg-abs_1.c
new file mode 100644
index
0000000000000000000000000000000000000000..f823013c3ddf6b3a266c3abfcbf2642fc2a75fa6
--- /dev/null
+++ b/gcc/testsuite/gcc.target/aarch64/fneg-abs_1.c
@@ -0,0 +1,39 @@
+/* { dg-do compile } */
+/* { dg-options "-O3" } */
+/* { dg-final { check-function-bodies "**" "" "" { target lp64 } } } */
+
+#pragma GCC target "+nosve"
+
+#include <arm_neon.h>
+
+/*
+** t1:
+** orr v[0-9]+.2s, #128, lsl #24
+** ret
+*/
+float32x2_t t1 (float32x2_t a)
+{
+ return vneg_f32 (vabs_f32 (a));
+}
+
+/*
+** t2:
+** orr v[0-9]+.4s, #128, lsl #24
+** ret
+*/
+float32x4_t t2 (float32x4_t a)
+{
+ return vnegq_f32 (vabsq_f32 (a));
+}
+
+/*
+** t3:
+** adrp x0, .LC[0-9]+
+** ldr q[0-9]+, \[x0, #:lo12:.LC0\]
+** orr v[0-9]+.16b, v[0-9]+.16b, v[0-9]+.16b
+** ret
+*/
+float64x2_t t3 (float64x2_t a)
+{
+ return vnegq_f64 (vabsq_f64 (a));
+}
diff --git a/gcc/testsuite/gcc.target/aarch64/fneg-abs_2.c
b/gcc/testsuite/gcc.target/aarch64/fneg-abs_2.c
new file mode 100644
index
0000000000000000000000000000000000000000..141121176b309e4b2aa413dc55271a6e3c93d5e1
--- /dev/null
+++ b/gcc/testsuite/gcc.target/aarch64/fneg-abs_2.c
@@ -0,0 +1,31 @@
+/* { dg-do compile } */
+/* { dg-options "-O3" } */
+/* { dg-final { check-function-bodies "**" "" "" { target lp64 } } } */
+
+#pragma GCC target "+nosve"
+
+#include <arm_neon.h>
+#include <math.h>
+
+/*
+** f1:
+** movi v[0-9]+.2s, 0x80, lsl 24
+** orr v[0-9]+.8b, v[0-9]+.8b, v[0-9]+.8b
+** ret
+*/
+float32_t f1 (float32_t a)
+{
+ return -fabsf (a);
+}
+
+/*
+** f2:
+** mov x0, -9223372036854775808
+** fmov d[0-9]+, x0
+** orr v[0-9]+.8b, v[0-9]+.8b, v[0-9]+.8b
+** ret
+*/
+float64_t f2 (float64_t a)
+{
+ return -fabs (a);
+}
diff --git a/gcc/testsuite/gcc.target/aarch64/fneg-abs_3.c
b/gcc/testsuite/gcc.target/aarch64/fneg-abs_3.c
new file mode 100644
index
0000000000000000000000000000000000000000..b4652173a95d104ddfa70c497f0627a61ea89d3b
--- /dev/null
+++ b/gcc/testsuite/gcc.target/aarch64/fneg-abs_3.c
@@ -0,0 +1,36 @@
+/* { dg-do compile } */
+/* { dg-options "-O3" } */
+/* { dg-final { check-function-bodies "**" "" "" { target lp64 } } } */
+
+#pragma GCC target "+nosve"
+
+#include <arm_neon.h>
+#include <math.h>
+
+/*
+** f1:
+** ...
+** ldr q[0-9]+, \[x0\]
+** orr v[0-9]+.4s, #128, lsl #24
+** str q[0-9]+, \[x0\], 16
+** ...
+*/
+void f1 (float32_t *a, int n)
+{
+ for (int i = 0; i < (n & -8); i++)
+ a[i] = -fabsf (a[i]);
+}
+
+/*
+** f2:
+** ...
+** ldr q[0-9]+, \[x0\]
+** orr v[0-9]+.16b, v[0-9]+.16b, v[0-9]+.16b
+** str q[0-9]+, \[x0\], 16
+** ...
+*/
+void f2 (float64_t *a, int n)
+{
+ for (int i = 0; i < (n & -8); i++)
+ a[i] = -fabs (a[i]);
+}
diff --git a/gcc/testsuite/gcc.target/aarch64/fneg-abs_4.c
b/gcc/testsuite/gcc.target/aarch64/fneg-abs_4.c
new file mode 100644
index
0000000000000000000000000000000000000000..10879dea74462d34b26160eeb0bd54ead063166b
--- /dev/null
+++ b/gcc/testsuite/gcc.target/aarch64/fneg-abs_4.c
@@ -0,0 +1,39 @@
+/* { dg-do compile } */
+/* { dg-options "-O3" } */
+/* { dg-final { check-function-bodies "**" "" "" { target lp64 } } } */
+
+#pragma GCC target "+nosve"
+
+#include <string.h>
+
+/*
+** negabs:
+** mov x0, -9223372036854775808
+** fmov d[0-9]+, x0
+** orr v[0-9]+.8b, v[0-9]+.8b, v[0-9]+.8b
+** ret
+*/
+double negabs (double x)
+{
+ unsigned long long y;
+ memcpy (&y, &x, sizeof(double));
+ y = y | (1UL << 63);
+ memcpy (&x, &y, sizeof(double));
+ return x;
+}
+
+/*
+** negabsf:
+** movi v[0-9]+.2s, 0x80, lsl 24
+** orr v[0-9]+.8b, v[0-9]+.8b, v[0-9]+.8b
+** ret
+*/
+float negabsf (float x)
+{
+ unsigned int y;
+ memcpy (&y, &x, sizeof(float));
+ y = y | (1U << 31);
+ memcpy (&x, &y, sizeof(float));
+ return x;
+}
+
diff --git a/gcc/testsuite/gcc.target/aarch64/sve/fneg-abs_1.c
b/gcc/testsuite/gcc.target/aarch64/sve/fneg-abs_1.c
new file mode 100644
index
0000000000000000000000000000000000000000..0c7664e6de77a497682952653ffd417453854d52
--- /dev/null
+++ b/gcc/testsuite/gcc.target/aarch64/sve/fneg-abs_1.c
@@ -0,0 +1,37 @@
+/* { dg-do compile } */
+/* { dg-options "-O3" } */
+/* { dg-final { check-function-bodies "**" "" "" { target lp64 } } } */
+
+#include <arm_neon.h>
+
+/*
+** t1:
+** orr v[0-9]+.2s, #128, lsl #24
+** ret
+*/
+float32x2_t t1 (float32x2_t a)
+{
+ return vneg_f32 (vabs_f32 (a));
+}
+
+/*
+** t2:
+** orr v[0-9]+.4s, #128, lsl #24
+** ret
+*/
+float32x4_t t2 (float32x4_t a)
+{
+ return vnegq_f32 (vabsq_f32 (a));
+}
+
+/*
+** t3:
+** adrp x0, .LC[0-9]+
+** ldr q[0-9]+, \[x0, #:lo12:.LC0\]
+** orr v[0-9]+.16b, v[0-9]+.16b, v[0-9]+.16b
+** ret
+*/
+float64x2_t t3 (float64x2_t a)
+{
+ return vnegq_f64 (vabsq_f64 (a));
+}
diff --git a/gcc/testsuite/gcc.target/aarch64/sve/fneg-abs_2.c
b/gcc/testsuite/gcc.target/aarch64/sve/fneg-abs_2.c
new file mode 100644
index
0000000000000000000000000000000000000000..a60cd31b9294af2dac69eed1c93f899bd5c78fca
--- /dev/null
+++ b/gcc/testsuite/gcc.target/aarch64/sve/fneg-abs_2.c
@@ -0,0 +1,29 @@
+/* { dg-do compile } */
+/* { dg-options "-O3" } */
+/* { dg-final { check-function-bodies "**" "" "" { target lp64 } } } */
+
+#include <arm_neon.h>
+#include <math.h>
+
+/*
+** f1:
+** movi v[0-9]+.2s, 0x80, lsl 24
+** orr v[0-9]+.8b, v[0-9]+.8b, v[0-9]+.8b
+** ret
+*/
+float32_t f1 (float32_t a)
+{
+ return -fabsf (a);
+}
+
+/*
+** f2:
+** mov x0, -9223372036854775808
+** fmov d[0-9]+, x0
+** orr v[0-9]+.8b, v[0-9]+.8b, v[0-9]+.8b
+** ret
+*/
+float64_t f2 (float64_t a)
+{
+ return -fabs (a);
+}
diff --git a/gcc/testsuite/gcc.target/aarch64/sve/fneg-abs_3.c
b/gcc/testsuite/gcc.target/aarch64/sve/fneg-abs_3.c
new file mode 100644
index
0000000000000000000000000000000000000000..1bf34328d8841de8e6b0a5458562a9f00e31c275
--- /dev/null
+++ b/gcc/testsuite/gcc.target/aarch64/sve/fneg-abs_3.c
@@ -0,0 +1,34 @@
+/* { dg-do compile } */
+/* { dg-options "-O3" } */
+/* { dg-final { check-function-bodies "**" "" "" { target lp64 } } } */
+
+#include <arm_neon.h>
+#include <math.h>
+
+/*
+** f1:
+** ...
+** ld1w z[0-9]+.s, p[0-9]+/z, \[x0, x2, lsl 2\]
+** orr z[0-9]+.s, z[0-9]+.s, #0x80000000
+** st1w z[0-9]+.s, p[0-9]+, \[x0, x2, lsl 2\]
+** ...
+*/
+void f1 (float32_t *a, int n)
+{
+ for (int i = 0; i < (n & -8); i++)
+ a[i] = -fabsf (a[i]);
+}
+
+/*
+** f2:
+** ...
+** ld1d z[0-9]+.d, p[0-9]+/z, \[x0, x2, lsl 3\]
+** orr z[0-9]+.d, z[0-9]+.d, #0x8000000000000000
+** st1d z[0-9]+.d, p[0-9]+, \[x0, x2, lsl 3\]
+** ...
+*/
+void f2 (float64_t *a, int n)
+{
+ for (int i = 0; i < (n & -8); i++)
+ a[i] = -fabs (a[i]);
+}
diff --git a/gcc/testsuite/gcc.target/aarch64/sve/fneg-abs_4.c
b/gcc/testsuite/gcc.target/aarch64/sve/fneg-abs_4.c
new file mode 100644
index
0000000000000000000000000000000000000000..21f2a8da2a5d44e3d01f6604ca7be87e3744d494
--- /dev/null
+++ b/gcc/testsuite/gcc.target/aarch64/sve/fneg-abs_4.c
@@ -0,0 +1,37 @@
+/* { dg-do compile } */
+/* { dg-options "-O3" } */
+/* { dg-final { check-function-bodies "**" "" "" { target lp64 } } } */
+
+#include <string.h>
+
+/*
+** negabs:
+** mov x0, -9223372036854775808
+** fmov d[0-9]+, x0
+** orr v[0-9]+.8b, v[0-9]+.8b, v[0-9]+.8b
+** ret
+*/
+double negabs (double x)
+{
+ unsigned long long y;
+ memcpy (&y, &x, sizeof(double));
+ y = y | (1UL << 63);
+ memcpy (&x, &y, sizeof(double));
+ return x;
+}
+
+/*
+** negabsf:
+** movi v[0-9]+.2s, 0x80, lsl 24
+** orr v[0-9]+.8b, v[0-9]+.8b, v[0-9]+.8b
+** ret
+*/
+float negabsf (float x)
+{
+ unsigned int y;
+ memcpy (&y, &x, sizeof(float));
+ y = y | (1U << 31);
+ memcpy (&x, &y, sizeof(float));
+ return x;
+}
+
rb17718.patch
Description: rb17718.patch
