git
/
gcc
mirror of git://gcc.gnu.org/git/gcc.git
1
0
Fork 0
Code Issues Packages Projects Releases Wiki Activity

builtins.c (expand_builtin_memcmp): don't swap args unless result is only being compared with zero. 

2016-09-29  Bernd Schmidt  <bschmidt@redhat.com>

	* builtins.c (expand_builtin_memcmp): don't swap args unless
	result is only being compared with zero.

From-SVN: r240625
This commit is contained in:
Bernd Schmidt 2016-09-29 11:21:20 -05:00 committed by Aaron Sawdey
parent 0b4b9552ee
commit d0d7f887b7
2 changed files with 12 additions and 5 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

5
gcc/ChangeLog
View File

@ -1,3 +1,8 @@
2016-09-29 Bernd Schmidt <bschmidt@redhat.com>
* builtins.c (expand_builtin_memcmp): don't swap args unless
result is only being compared with zero.
2016-09-29 Marek Polacek <polacek@redhat.com> 2016-09-29 Marek Polacek <polacek@redhat.com>
* dwarf2out.c (loc_descriptor): Add fall through comment. * dwarf2out.c (loc_descriptor): Add fall through comment.

12
gcc/builtins.c
View File

@ -3707,11 +3707,13 @@ expand_builtin_memcmp (tree exp, rtx target, bool result_eq)
by_pieces_constfn constfn = NULL; by_pieces_constfn constfn = NULL;
const char *src_str = c_getstr (arg1); const char *src_str = c_getstr (arg2);
if (src_str == NULL) if (result_eq && src_str == NULL)
src_str = c_getstr (arg2); {
else src_str = c_getstr (arg1);
std::swap (arg1_rtx, arg2_rtx); if (src_str != NULL)
std::swap (arg1_rtx, arg2_rtx);
}
/* If SRC is a string constant and block move would be done /* If SRC is a string constant and block move would be done
by pieces, we can avoid loading the string from memory by pieces, we can avoid loading the string from memory