[gcc r12-5378] middle-end: check that both sides of complex expression is a mul.

[gcc r12-5378] middle-end: check that both sides of complex expression is a mul.

[Tamar Christina]

https://gcc.gnu.org/g:4f0a2f5a3ddb1024b885c066a18caae4d733bb6c

commit r12-5378-g4f0a2f5a3ddb1024b885c066a18caae4d733bb6c
Author: Tamar Christina <tamar.christina@arm.com>
Date:   Thu Nov 18 17:10:36 2021 +0000

    middle-end: check that both sides of complex expression is a mul.
    
    Both sides of the VEC_PERM_EXPR need to be a MULT but the check
    was accidentally checking if both sides are a mul.
    
    The FMS case would be handled by the validate_multiplication but
    this makes the requirement more explicit and we exit earlier.
    
    gcc/ChangeLog:
    
            PR tree-optimization/103311
            * tree-vect-slp-patterns.c (complex_mul_pattern::matches,
            complex_fms_pattern::matches): Check for multiplications.
    
    gcc/testsuite/ChangeLog:
    
            PR tree-optimization/103311
            * gcc.target/aarch64/pr103311.c: New test.

Diff:
---
 gcc/testsuite/gcc.target/aarch64/pr103311.c | 16 ++++++++++++++++
 gcc/tree-vect-slp-patterns.c                |  6 ++++--
 2 files changed, 20 insertions(+), 2 deletions(-)

diff --git a/gcc/testsuite/gcc.target/aarch64/pr103311.c b/gcc/testsuite/gcc.target/aarch64/pr103311.c
new file mode 100644
index 00000000000..7bcc7db79be
--- /dev/null
+++ b/gcc/testsuite/gcc.target/aarch64/pr103311.c
@@ -0,0 +1,16 @@
+/* { dg-do compile } */
+/* { dg-require-effective-target arm_v8_3a_complex_neon_ok } */
+/* { dg-add-options arm_v8_3a_complex_neon } */
+/* { dg-additional-options "-std=c99" } */
+
+_Complex double y;
+
+void
+cbknu (_Complex double f)
+{
+  const _Complex double cone = 1.0e0;
+
+  f = f * cone;
+  y = f * cone;
+}
+
diff --git a/gcc/tree-vect-slp-patterns.c b/gcc/tree-vect-slp-patterns.c
index 53fbe5185f5..d916fc9cef9 100644
--- a/gcc/tree-vect-slp-patterns.c
+++ b/gcc/tree-vect-slp-patterns.c
@@ -949,7 +949,7 @@ complex_mul_pattern::matches (complex_operation_t op,
 
   bool mul0 = vect_match_expression_p (l0node[0], MULT_EXPR);
   bool mul1 = vect_match_expression_p (l0node[1], MULT_EXPR);
-  if (!mul0 && !mul1)
+  if (!mul0 || !mul1)
     return IFN_LAST;
 
   /* Now operand2+4 may lead to another expression.  */
@@ -1204,7 +1204,9 @@ complex_fms_pattern::matches (complex_operation_t op,
 
   /* If these nodes don't have any children then they're
      not ones we're interested in.  */
-  if (left_op.length () != 2 || right_op.length () != 2)
+  if (left_op.length () != 2
+      || right_op.length () != 2
+      || !vect_match_expression_p (l0node[1], MULT_EXPR))
     return IFN_LAST;
 
   bool is_neg = vect_normalize_conj_loc (left_op);