http://gcc.gnu.org/bugzilla/show_bug.cgi?id=56719
Bug #: 56719
Summary: missed optimization: i > 0xffff || i*4 > 0xffff
Classification: Unclassified
Product: gcc
Version: 4.7.2
Status: UNCONFIRMED
Severity: normal
Priority: P3
Component: rtl-optimization
AssignedTo: [email protected]
ReportedBy: [email protected]
This is the test code:
int foo(unsigned int i) {
if (i > 0xffff || i*4 > 0xffff)
baz();
}
gcc -O2 generates a cmp, a shift, and another cmp.
Why does this not generate a single cmp with 0x3fff?