mirror of
https://github.com/c64scene-ar/llvm-6502.git
synced 2025-01-14 00:32:55 +00:00
92b38a9d1c
This generalizes the code to eliminate extra truncs/exts around i1 bit
operations to also do the same on PPC64 for i32 bit operations. This eliminates
a fairly prevalent code wart:
int foo(int a) {
return a == 5 ? 7 : 8;
}
On PPC64, because of the extension implied by the ABI, this would generate:
cmplwi 0, 3, 5
li 12, 8
li 4, 7
isel 3, 4, 12, 2
rldicl 3, 3, 0, 32
blr
where the 'rldicl 3, 3, 0, 32', the extension, is completely unnecessary. At
least for the single-BB case (which is all that the DAG combine mechanism can
handle), this unnecessary extension is no longer generated.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@202600 91177308-0d34-0410-b5e6-96231b3b80d8