[gcc r10-10501] target/104453 - guard call folding with NULL LHS

[gcc r10-10501] target/104453 - guard call folding with NULL LHS

[Richard Biener]

https://gcc.gnu.org/g:807bfd4357609655c81d0a3282b699b10e7aeb5a

commit r10-10501-g807bfd4357609655c81d0a3282b699b10e7aeb5a
Author: Richard Biener <rguenther@suse.de>
Date:   Wed Feb 9 08:48:35 2022 +0100

    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.c (ix86_gimple_fold_builtin): Guard shift
            folding for NULL LHS.
    
            * gcc.target/i386/pr104453.c: New testcase.
    
    (cherry picked from commit 1c827873ed283df282f2df11dfe0ff607e07dab3)

Diff:
---
 gcc/config/i386/i386.c                   |  2 ++
 gcc/testsuite/gcc.target/i386/pr104453.c | 11 +++++++++++
 2 files changed, 13 insertions(+)

diff --git a/gcc/config/i386/i386.c b/gcc/config/i386/i386.c
index cec0340ec51..19cb5d40c69 100644
--- a/gcc/config/i386/i386.c
+++ b/gcc/config/i386/i386.c
@@ -17848,6 +17848,8 @@ 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);
       if (n_args > 2)
diff --git a/gcc/testsuite/gcc.target/i386/pr104453.c b/gcc/testsuite/gcc.target/i386/pr104453.c
new file mode 100644
index 00000000000..325cedf0e2c
--- /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);
+}