http://gcc.gnu.org/bugzilla/show_bug.cgi?id=55152
Bug #: 55152
Summary: MAX_EXPR(a,-a) is really ABS_EXPR(a)
Classification: Unclassified
Product: gcc
Version: 4.8.0
Status: UNCONFIRMED
Severity: normal
Priority: P3
Component: middle-end
AssignedTo: [email protected]
ReportedBy: [email protected]
I tried compiling this code with -Ofast, but *.optimized still only contained a
MAX_EXPR and not an ABS_EXPR (the back-end didn't find the optimization
either).
double f(double a){
return (a>=-a)?a:-a;
}
It seems that some simple code in fold-const.c could help (fold is called from
the front-end for COND_EXPR), not sure if anything would call it if -a went
though a temporary variable though.
