[gcc r14-2092] Avoid shorten_binary_op on VECTOR_TYPE

[Richard Biener]

https://gcc.gnu.org/g:5b3d421be747386349981c6291f0af1756b1112c

commit r14-2092-g5b3d421be747386349981c6291f0af1756b1112c
Author: Richard Biener <rguenther@suse.de>
Date:   Fri Jun 23 10:01:38 2023 +0200

    Avoid shorten_binary_op on VECTOR_TYPE
    
    When we disallow TYPE_PRECISION on VECTOR_TYPEs it shows that
    shorten_binary_op performs some checks on that that are likely
    harmless in the end.  The following bails out early for
    VECTOR_TYPE operations to avoid those questionable checks.
    
    gcc/c-family/
            * c-common.cc (shorten_binary_op): Exit early for VECTOR_TYPE
            operations.

Diff:
---
 gcc/c-family/c-common.cc | 4 ++++
 1 file changed, 4 insertions(+)

diff --git a/gcc/c-family/c-common.cc b/gcc/c-family/c-common.cc
index 9c8eed5442a..34566a342bd 100644
--- a/gcc/c-family/c-common.cc
+++ b/gcc/c-family/c-common.cc
@@ -1338,6 +1338,10 @@ shorten_binary_op (tree result_type, tree op0, tree op1, bool bitwise)
   int uns;
   tree type;
 
+  /* Do not shorten vector operations.  */
+  if (VECTOR_TYPE_P (result_type))
+    return result_type;
+
   /* Cast OP0 and OP1 to RESULT_TYPE.  Doing so prevents
      excessive narrowing when we call get_narrower below.  For
      example, suppose that OP0 is of unsigned int extended