This improves the `A CMP 0 ? A : -A` set of match patterns to use
bitwise_equal_p which allows an nop cast between signed and unsigned.
This allows catching a few extra cases which were not being caught before.
OK? Bootstrapped and tested on x86_64-linux-gnu with no regressions.
gcc/ChangeLog:
PR tree-optimization/101541
* match.pd (A CMP 0 ? A : -A): Improve
using bitwise_equal_p.
gcc/testsuite/ChangeLog:
PR tree-optimization/101541
* gcc.dg/tree-ssa/phi-opt-36.c: New test.
* gcc.dg/tree-ssa/phi-opt-37.c: New test.
---
gcc/match.pd | 49 ++++++++++++---------
gcc/testsuite/gcc.dg/tree-ssa/phi-opt-36.c | 51 ++++++++++++++++++++++
gcc/testsuite/gcc.dg/tree-ssa/phi-opt-37.c | 24 ++++++++++
3 files changed, 104 insertions(+), 20 deletions(-)
create mode 100644 gcc/testsuite/gcc.dg/tree-ssa/phi-opt-36.c
create mode 100644 gcc/testsuite/gcc.dg/tree-ssa/phi-opt-37.c
diff --git a/gcc/match.pd b/gcc/match.pd
index 45624f3dcb4..142e2dfbeb1 100644
--- a/gcc/match.pd
+++ b/gcc/match.pd
@@ -5668,42 +5668,51 @@ DEFINE_INT_AND_FLOAT_ROUND_FN (RINT)
/* A == 0 ? A : -A same as -A */
(for cmp (eq uneq)
(simplify
- (cnd (cmp @0 zerop) @0 (negate@1 @0))
- (if (!HONOR_SIGNED_ZEROS (type))
+ (cnd (cmp @0 zerop) @2 (negate@1 @2))
+ (if (!HONOR_SIGNED_ZEROS (type)
+ && bitwise_equal_p (@0, @2))
@1))
(simplify
- (cnd (cmp @0 zerop) zerop (negate@1 @0))
- (if (!HONOR_SIGNED_ZEROS (type))
+ (cnd (cmp @0 zerop) zerop (negate@1 @2))
+ (if (!HONOR_SIGNED_ZEROS (type)
+ && bitwise_equal_p (@0, @2))
@1))
)
/* A != 0 ? A : -A same as A */
(for cmp (ne ltgt)
(simplify
- (cnd (cmp @0 zerop) @0 (negate @0))
- (if (!HONOR_SIGNED_ZEROS (type))
- @0))
+ (cnd (cmp @0 zerop) @1 (negate @1))
+ (if (!HONOR_SIGNED_ZEROS (type)
+ && bitwise_equal_p (@0, @1))
+ @1))
(simplify
- (cnd (cmp @0 zerop) @0 integer_zerop)
- (if (!HONOR_SIGNED_ZEROS (type))
- @0))
+ (cnd (cmp @0 zerop) @1 integer_zerop)
+ (if (!HONOR_SIGNED_ZEROS (type)
+ && bitwise_equal_p (@0, @1))
+ @1))
)
/* A >=/> 0 ? A : -A same as abs (A) */
(for cmp (ge gt)
(simplify
- (cnd (cmp @0 zerop) @0 (negate @0))
- (if (!HONOR_SIGNED_ZEROS (type)
- && !TYPE_UNSIGNED (type))
- (abs @0))))
+ (cnd (cmp @0 zerop) @1 (negate @1))
+ (if (!HONOR_SIGNED_ZEROS (TREE_TYPE(@0))
+ && !TYPE_UNSIGNED (TREE_TYPE(@0))
+ && bitwise_equal_p (@0, @1))
+ (if (TYPE_UNSIGNED (type))
+ (absu:type @0)
+ (abs @0)))))
/* A <=/< 0 ? A : -A same as -abs (A) */
(for cmp (le lt)
(simplify
- (cnd (cmp @0 zerop) @0 (negate @0))
- (if (!HONOR_SIGNED_ZEROS (type)
- && !TYPE_UNSIGNED (type))
- (if (ANY_INTEGRAL_TYPE_P (type)
- && !TYPE_OVERFLOW_WRAPS (type))
+ (cnd (cmp @0 zerop) @1 (negate @1))
+ (if (!HONOR_SIGNED_ZEROS (TREE_TYPE(@0))
+ && !TYPE_UNSIGNED (TREE_TYPE(@0))
+ && bitwise_equal_p (@0, @1))
+ (if ((ANY_INTEGRAL_TYPE_P (TREE_TYPE (@0))
+ && !TYPE_OVERFLOW_WRAPS (TREE_TYPE (@0)))
+ || TYPE_UNSIGNED (type))
(with {
- tree utype = unsigned_type_for (type);
+ tree utype = unsigned_type_for (TREE_TYPE(@0));
}
(convert (negate (absu:utype @0))))
(negate (abs @0)))))
diff --git a/gcc/testsuite/gcc.dg/tree-ssa/phi-opt-36.c
b/gcc/testsuite/gcc.dg/tree-ssa/phi-opt-36.c
new file mode 100644
index 00000000000..4baf9f82a22
--- /dev/null
+++ b/gcc/testsuite/gcc.dg/tree-ssa/phi-opt-36.c
@@ -0,0 +1,51 @@
+/* { dg-options "-O2 -fdump-tree-phiopt" } */
+
+unsigned f0(int A)
+{
+ unsigned t = A;
+// A == 0? A : -A same as -A
+ if (A == 0) return t;
+ return -t;
+}
+
+unsigned f1(int A)
+{
+ unsigned t = A;
+// A != 0? A : -A same as A
+ if (A != 0) return t;
+ return -t;
+}
+unsigned f2(int A)
+{
+ unsigned t = A;
+// A >= 0? A : -A same as abs (A)
+ if (A >= 0) return t;
+ return -t;
+}
+unsigned f3(int A)
+{
+ unsigned t = A;
+// A > 0? A : -A same as abs (A)
+ if (A > 0) return t;
+ return -t;
+}
+unsigned f4(int A)
+{
+ unsigned t = A;
+// A <= 0? A : -A same as -abs (A)
+ if (A <= 0) return t;
+ return -t;
+}
+unsigned f5(int A)
+{
+ unsigned t = A;
+// A < 0? A : -A same as -abs (A)
+ if (A < 0) return t;
+ return -t;
+}
+
+/* f4 and f5 are not allowed to be optimized in early phi-opt. */
+/* { dg-final { scan-tree-dump-times "if " 2 "phiopt1" } } */
+/* { dg-final { scan-tree-dump-not "if " "phiopt2" } } */
+
+
diff --git a/gcc/testsuite/gcc.dg/tree-ssa/phi-opt-37.c
b/gcc/testsuite/gcc.dg/tree-ssa/phi-opt-37.c
new file mode 100644
index 00000000000..f1ff472aaff
--- /dev/null
+++ b/gcc/testsuite/gcc.dg/tree-ssa/phi-opt-37.c
@@ -0,0 +1,24 @@
+/* { dg-do compile } */
+/* { dg-options "-O1 -fdump-tree-phiopt1" } */
+
+unsigned abs_with_convert0 (int x)
+{
+ unsigned int y = x;
+
+ if (x < 0)
+ y = -y;
+
+ return y;
+}
+unsigned abs_with_convert1 (unsigned x)
+{
+ int y = x;
+
+ if (y < 0)
+ x = -x;
+
+ return x;
+}
+
+/* { dg-final { scan-tree-dump-times "ABSU_EXPR <" 2 "phiopt1" } } */
+/* { dg-final { scan-tree-dump-not "if " "phiopt1" } } */
--
2.39.3
