llvm-6502/test/CodeGen/X86/remat-mov-0.ll
Dan Gohman a10756ee65 Re-implement the main strength-reduction portion of LoopStrengthReduction.
This new version is much more aggressive about doing "full" reduction in
cases where it reduces register pressure, and also more aggressive about
rewriting induction variables to count down (or up) to zero when doing so
reduces register pressure.

It currently uses fairly simplistic algorithms for finding reuse
opportunities, but it introduces a new framework allows it to combine
multiple strategies at once to form hybrid solutions, instead of doing
all full-reduction or all base+index.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@94061 91177308-0d34-0410-b5e6-96231b3b80d8
2010-01-21 02:09:26 +00:00

34 lines
594 B
LLVM

; RUN: llc < %s -march=x86-64 | FileCheck %s
; CodeGen should remat the zero instead of spilling it.
declare void @foo(i64 %p)
; CHECK: bar:
; CHECK: xorl %edi, %edi
; CHECK: xorl %edi, %edi
define void @bar() nounwind {
call void @foo(i64 0)
call void @foo(i64 0)
ret void
}
; CHECK: bat:
; CHECK: movq $-1, %rdi
; CHECK: movq $-1, %rdi
define void @bat() nounwind {
call void @foo(i64 -1)
call void @foo(i64 -1)
ret void
}
; CHECK: bau:
; CHECK: movl $1, %edi
; CHECK: movl $1, %edi
define void @bau() nounwind {
call void @foo(i64 1)
call void @foo(i64 1)
ret void
}