target/104453 - guard call folding with NULL LHS

This guards shift builtin folding to do nothing when there is
no LHS, similar to what other foldings do.

2022-02-09  Richard Biener  <rguenther@suse.de>

	PR target/104453
	* config/i386/i386.cc (ix86_gimple_fold_builtin): Guard shift
	folding for NULL LHS.

	* gcc.target/i386/pr104453.c: New testcase.

diff --git a/gcc/config/i386/i386.cc b/gcc/config/i386/i386.cc
index dd5584fb8edfaec3d46a868c6ebc2844e3fccf6e..448c079c7ac21665da8fcafe7d52db3eb1829511 100644 (file)
--- a/gcc/config/i386/i386.cc
+++ b/gcc/config/i386/i386.cc
@@ -18642,6 +18642,8 @@ ix86_gimple_fold_builtin (gimple_stmt_iterator *gsi)
 
     do_shift:
       gcc_assert (n_args >= 2);
+      if (!gimple_call_lhs (stmt))
+       break;
       arg0 = gimple_call_arg (stmt, 0);
       arg1 = gimple_call_arg (stmt, 1);
       elems = TYPE_VECTOR_SUBPARTS (TREE_TYPE (arg0));

diff --git a/gcc/testsuite/gcc.target/i386/pr104453.c b/gcc/testsuite/gcc.target/i386/pr104453.c
new file mode 100644 (file)
index 0000000..325cedf
--- /dev/null
+++ b/gcc/testsuite/gcc.target/i386/pr104453.c
@@ -0,0 +1,11 @@
+/* { dg-do compile } */
+/* { dg-options "-mavx512f" } */
+
+typedef short __attribute__((__vector_size__ (32))) V;
+V g;
+
+void
+foo (void)
+{
+  __builtin_ia32_psrawi256 (g, 0);
+}