llvm-project/llvm/test/Transforms/ScalarRepl/2008-09-22-vector-gep.ll

26 lines
1.1 KiB
LLVM

; This test checks to see if scalarrepl also works when a gep with all zeroes is
; used instead of a bitcast to prepare a memmove pointer argument. Previously,
; this would not work when there was a vector involved in the struct, preventing
; scalarrepl from removing the alloca below.
; RUN: opt < %s -scalarrepl -S > %t
; RUN: cat %t | not grep alloca
target datalayout = "E-p:64:64:64-i1:8:8-i8:8:8-i16:16:16-i32:32:32-i64:32:64-f32:32:32-f64:64:64-v64:64:64-v128:128:128-a0:0:64"
%struct.two = type <{ < 2 x i8 >, i16 }>
define void @main(%struct.two* %D, i16 %V) {
entry:
%S = alloca %struct.two
%S.2 = getelementptr %struct.two* %S, i32 0, i32 1
store i16 %V, i16* %S.2
; This gep is effectively a bitcast to i8*, but is sometimes generated
; because the type of the first element in %struct.two is i8.
%tmpS = getelementptr %struct.two* %S, i32 0, i32 0, i32 0
%tmpD = bitcast %struct.two* %D to i8*
call void @llvm.memmove.p0i8.p0i8.i32(i8* %tmpD, i8* %tmpS, i32 4, i32 1, i1 false)
ret void
}
declare void @llvm.memmove.p0i8.p0i8.i32(i8* nocapture, i8* nocapture, i32, i32, i1) nounwind