[glibc] Sync intprops.h from Gnulib

[glibc] Sync intprops.h from Gnulib

[Paul Eggert]

https://sourceware.org/git/gitweb.cgi?p=glibc.git;h=7279f0a282283db04352e247c3bdb39ee03d10f6

commit 7279f0a282283db04352e247c3bdb39ee03d10f6
Author: Paul Eggert <eggert@cs.ucla.edu>
Date:   Tue Aug 4 22:58:58 2020 -0700

    Sync intprops.h from Gnulib
    
    * include/intprops.h: Sync from Gnulib.  This improves
    performance of INT_MULTIPLY_WRAPV on recent GCC, which affects
    glibc only in the support library.

Diff:
---
 include/intprops.h | 17 +++++++++++------
 1 file changed, 11 insertions(+), 6 deletions(-)

diff --git a/include/intprops.h b/include/intprops.h
index 0c379a8c5b..6de65b067d 100644
--- a/include/intprops.h
+++ b/include/intprops.h
@@ -373,12 +373,17 @@
    _GL_INT_OP_WRAPV (a, b, r, -, _GL_INT_SUBTRACT_RANGE_OVERFLOW)
 #endif
 #if _GL_HAS_BUILTIN_MUL_OVERFLOW
-/* Work around GCC bug 91450.  */
-# define INT_MULTIPLY_WRAPV(a, b, r) \
-   ((!_GL_SIGNED_TYPE_OR_EXPR (*(r)) && EXPR_SIGNED (a) && EXPR_SIGNED (b) \
-     && _GL_INT_MULTIPLY_RANGE_OVERFLOW (a, b, 0, (__typeof__ (*(r))) -1)) \
-    ? ((void) __builtin_mul_overflow (a, b, r), 1) \
-    : __builtin_mul_overflow (a, b, r))
+# if (9 < __GNUC__ + (3 <= __GNUC_MINOR__) \
+      || (__GNUC__ == 8 && 4 <= __GNUC_MINOR__))
+#  define INT_MULTIPLY_WRAPV(a, b, r) __builtin_mul_overflow (a, b, r)
+# else
+   /* Work around GCC bug 91450.  */
+#  define INT_MULTIPLY_WRAPV(a, b, r) \
+    ((!_GL_SIGNED_TYPE_OR_EXPR (*(r)) && EXPR_SIGNED (a) && EXPR_SIGNED (b) \
+      && _GL_INT_MULTIPLY_RANGE_OVERFLOW (a, b, 0, (__typeof__ (*(r))) -1)) \
+     ? ((void) __builtin_mul_overflow (a, b, r), 1) \
+     : __builtin_mul_overflow (a, b, r))
+# endif
 #else
 # define INT_MULTIPLY_WRAPV(a, b, r) \
    _GL_INT_OP_WRAPV (a, b, r, *, _GL_INT_MULTIPLY_RANGE_OVERFLOW)