last night, breaking crafty and twolf. Make sure that the newly found
legal nodes are themselves not re-legalized until the next iteration.
Also, since this functionality exists now, we can reduce number of legalizer
iterations by depending on this behavior instead of having to misuse 'do
another iteration' to get the same effect.
llvm-svn: 24875
load. This reduces number of worklist iterations and avoid missing optimizations
depending on folding of things into sext_inreg nodes (which aren't supported by
all targets).
Tested by Regression/CodeGen/X86/extend.ll:test2
llvm-svn: 24712
Allow (zext (truncate)) to apply after legalize if the target supports
AND (which all do).
This compiles
short %foo() {
%tmp.0 = load ubyte* %X ; <ubyte> [#uses=1]
%tmp.3 = cast ubyte %tmp.0 to short ; <short> [#uses=1]
ret short %tmp.3
}
to:
_foo:
movzbl _X, %eax
ret
instead of:
_foo:
movzbl _X, %eax
movzbl %al, %eax
ret
thanks to Evan for pointing this out.
llvm-svn: 24709
1. Only forward subst offsets into loads and stores, not into arbitrary
things, where it will likely become a load.
2. If the source is a cast from pointer, forward subst the cast as well,
allowing us to fold the cast away (improving cases when the cast is
from an alloca or global).
This hasn't been fully tested, but does appear to further reduce register
pressure and improve code. Lets let the testers grind on it a bit. :)
llvm-svn: 24640
