https://gcc.gnu.org/g:39d56b96996dd8336652ceac97983c26fd8de4c6
commit r12-10431-g39d56b96996dd8336652ceac97983c26fd8de4c6
Author: Andrew Pinski <apin...@marvell.com>
Date: Thu Sep 7 22:13:31 2023 -0700
Fix PR 111331: wrong code for `a > 28 ? MIN<a, 28> : 29`
The problem here is after r6-7425-ga9fee7cdc3c62d0e51730,
the comparison to see if the transformation could be done was using the
wrong value. Instead of see if the inner was LE (for MIN and GE for MAX)
the outer value, it was comparing the inner to the value used in the
comparison
which was wrong.
Committed to GCC 13 branch after bootstrapped and tested on
x86_64-linux-gnu.
gcc/ChangeLog:
PR tree-optimization/111331
* tree-ssa-phiopt.cc (minmax_replacement):
Fix the LE/GE comparison for the
`(a CMP CST1) ? max<a,CST2> : a` optimization.
gcc/testsuite/ChangeLog:
PR tree-optimization/111331
* gcc.c-torture/execute/pr111331-1.c: New test.
* gcc.c-torture/execute/pr111331-2.c: New test.
* gcc.c-torture/execute/pr111331-3.c: New test.
(cherry picked from commit 30e6ee074588bacefd2dfe745b188bb20c81fe5e)
Diff:
---
gcc/testsuite/gcc.c-torture/execute/pr111331-1.c | 17 +++++++++++++++++
gcc/testsuite/gcc.c-torture/execute/pr111331-2.c | 19 +++++++++++++++++++
gcc/testsuite/gcc.c-torture/execute/pr111331-3.c | 15 +++++++++++++++
gcc/tree-ssa-phiopt.cc | 8 ++++----
4 files changed, 55 insertions(+), 4 deletions(-)
diff --git a/gcc/testsuite/gcc.c-torture/execute/pr111331-1.c
b/gcc/testsuite/gcc.c-torture/execute/pr111331-1.c
new file mode 100644
index 000000000000..4c7f4fdbaa9d
--- /dev/null
+++ b/gcc/testsuite/gcc.c-torture/execute/pr111331-1.c
@@ -0,0 +1,17 @@
+int a;
+int b;
+int c(int d, int e, int f) {
+ if (d < e)
+ return e;
+ if (d > f)
+ return f;
+ return d;
+}
+int main() {
+ int g = -1;
+ a = c(b + 30, 29, g + 29);
+ volatile t = a;
+ if (t != 28)
+ __builtin_abort();
+ return 0;
+}
diff --git a/gcc/testsuite/gcc.c-torture/execute/pr111331-2.c
b/gcc/testsuite/gcc.c-torture/execute/pr111331-2.c
new file mode 100644
index 000000000000..5c677f2caa9f
--- /dev/null
+++ b/gcc/testsuite/gcc.c-torture/execute/pr111331-2.c
@@ -0,0 +1,19 @@
+
+int a;
+int b;
+
+int main() {
+ int d = b+30;
+ {
+ int t;
+ if (d < 29)
+ t = 29;
+ else
+ t = (d > 28) ? 28 : d;
+ a = t;
+ }
+ volatile int t = a;
+ if (a != 28)
+ __builtin_abort();
+ return 0;
+}
diff --git a/gcc/testsuite/gcc.c-torture/execute/pr111331-3.c
b/gcc/testsuite/gcc.c-torture/execute/pr111331-3.c
new file mode 100644
index 000000000000..213d9bdd539d
--- /dev/null
+++ b/gcc/testsuite/gcc.c-torture/execute/pr111331-3.c
@@ -0,0 +1,15 @@
+int a;
+int b;
+
+int main() {
+ int d = b+30;
+ {
+ int t;
+ t = d < 29 ? 29 : ((d > 28) ? 28 : d);
+ a = t;
+ }
+ volatile int t = a;
+ if (a != 28)
+ __builtin_abort();
+ return 0;
+}
diff --git a/gcc/tree-ssa-phiopt.cc b/gcc/tree-ssa-phiopt.cc
index c56d0b9ff151..e2dba56383b4 100644
--- a/gcc/tree-ssa-phiopt.cc
+++ b/gcc/tree-ssa-phiopt.cc
@@ -2014,7 +2014,7 @@ minmax_replacement (basic_block cond_bb, basic_block
middle_bb,
/* We need BOUND <= LARGER. */
if (!integer_nonzerop (fold_build2 (LE_EXPR, boolean_type_node,
- bound, larger)))
+ bound, arg_false)))
return false;
}
else if (operand_equal_for_phi_arg_p (arg_false, smaller)
@@ -2045,7 +2045,7 @@ minmax_replacement (basic_block cond_bb, basic_block
middle_bb,
/* We need BOUND >= SMALLER. */
if (!integer_nonzerop (fold_build2 (GE_EXPR, boolean_type_node,
- bound, smaller)))
+ bound, arg_false)))
return false;
}
else
@@ -2085,7 +2085,7 @@ minmax_replacement (basic_block cond_bb, basic_block
middle_bb,
/* We need BOUND >= LARGER. */
if (!integer_nonzerop (fold_build2 (GE_EXPR, boolean_type_node,
- bound, larger)))
+ bound, arg_true)))
return false;
}
else if (operand_equal_for_phi_arg_p (arg_true, smaller)
@@ -2112,7 +2112,7 @@ minmax_replacement (basic_block cond_bb, basic_block
middle_bb,
/* We need BOUND <= SMALLER. */
if (!integer_nonzerop (fold_build2 (LE_EXPR, boolean_type_node,
- bound, smaller)))
+ bound, arg_true)))
return false;
}
else
