llvm/test/CodeGen/PowerPC/unal-vec-negarith.ll
Hal Finkel c2a163944a [PowerPC] Compute the MMO offset for an unaligned load with signed arithmetic
If you compute the MMO offset using unsigned arithmetic, you end up with a
large positive offset instead of a small negative one. In theory, this could
cause bad instruction-scheduling decisions later.

I noticed this by inspection from the debug output, and using that for the
regression test is the best I can do right now.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@246805 91177308-0d34-0410-b5e6-96231b3b80d8
2015-09-03 21:12:15 +00:00

18 lines
503 B
LLVM

; RUN: llc -debug-only=isel <%s >%t 2>&1 && FileCheck <%t %s
; REQUIRES: asserts
target datalayout = "E-m:e-i64:64-n32:64"
target triple = "powerpc64-unknown-linux-gnu"
define <16 x i8> @test_l_v16i8(<16 x i8>* %p) #0 {
entry:
%r = load <16 x i8>, <16 x i8>* %p, align 1
ret <16 x i8> %r
; CHECK-NOT: v4i32,ch = llvm.ppc.altivec.lvx{{.*}}<LD31[%p+4294967281](align=1)>
; CHECK: v4i32,ch = llvm.ppc.altivec.lvx{{.*}}<LD31[%p+-15](align=1)>
}
attributes #0 = { nounwind "target-cpu"="pwr7" }