llvm-project/llvm/test/Transforms/DeadStoreElimination/overlap.ll

128 lines
3.8 KiB
LLVM

; NOTE: Assertions have been autogenerated by utils/update_test_checks.py
; RUN: opt < %s -basic-aa -dse -S | FileCheck %s
; RUN: opt < %s -aa-pipeline=basic-aa -passes=dse -S | FileCheck %s
declare void @use(i64*)
define void @test1() {
; CHECK-LABEL: @test1(
; CHECK-NEXT: [[A:%.*]] = alloca i64, align 8
; CHECK-NEXT: call void @use(i64* [[A]])
; CHECK-NEXT: [[PTR1:%.*]] = bitcast i64* [[A]] to i8*
; CHECK-NEXT: [[PTR2:%.*]] = getelementptr i8, i8* [[PTR1]], i32 1
; CHECK-NEXT: store i8 10, i8* [[PTR1]], align 1
; CHECK-NEXT: store i8 20, i8* [[PTR2]], align 1
; CHECK-NEXT: [[LV:%.*]] = load i64, i64* [[A]], align 4
; CHECK-NEXT: store i8 0, i8* [[PTR1]], align 1
; CHECK-NEXT: call void @use(i64* [[A]])
; CHECK-NEXT: ret void
;
%a = alloca i64
call void @use(i64* %a)
%ptr1 = bitcast i64* %a to i8*
%ptr2 = getelementptr i8, i8* %ptr1, i32 1
store i8 10, i8* %ptr1
store i8 20, i8* %ptr2
%lv = load i64, i64* %a
store i8 0, i8* %ptr1
call void @use(i64* %a)
ret void
}
define void @test2() {
; CHECK-LABEL: @test2(
; CHECK-NEXT: [[A:%.*]] = alloca i64, align 8
; CHECK-NEXT: call void @use(i64* [[A]])
; CHECK-NEXT: [[PTR1:%.*]] = bitcast i64* [[A]] to i8*
; CHECK-NEXT: [[PTR2:%.*]] = getelementptr i8, i8* [[PTR1]], i32 1
; CHECK-NEXT: store i8 10, i8* [[PTR1]], align 1
; CHECK-NEXT: store i8 20, i8* [[PTR2]], align 1
; CHECK-NEXT: br i1 undef, label [[BB1:%.*]], label [[END:%.*]]
; CHECK: bb1:
; CHECK-NEXT: [[LV:%.*]] = load i64, i64* [[A]], align 4
; CHECK-NEXT: br label [[END]]
; CHECK: end:
; CHECK-NEXT: store i8 0, i8* [[PTR1]], align 1
; CHECK-NEXT: call void @use(i64* [[A]])
; CHECK-NEXT: ret void
;
%a = alloca i64
call void @use(i64* %a)
%ptr1 = bitcast i64* %a to i8*
%ptr2 = getelementptr i8, i8* %ptr1, i32 1
store i8 10, i8* %ptr1
store i8 20, i8* %ptr2
br i1 undef, label %bb1, label %end
bb1:
%lv = load i64, i64* %a
br label %end
end:
store i8 0, i8* %ptr1
call void @use(i64* %a)
ret void
}
; The store to %a0 is dead, because only %a1 is read later.
define void @test3(i1 %c) {
; CHECK-LABEL: @test3(
; CHECK-NEXT: [[A:%.*]] = alloca [2 x i8], align 1
; CHECK-NEXT: [[A1:%.*]] = getelementptr [2 x i8], [2 x i8]* [[A]], i32 0, i32 1
; CHECK-NEXT: br i1 [[C:%.*]], label [[IF:%.*]], label [[ELSE:%.*]]
; CHECK: if:
; CHECK-NEXT: store [2 x i8] zeroinitializer, [2 x i8]* [[A]], align 1
; CHECK-NEXT: br label [[ELSE]]
; CHECK: else:
; CHECK-NEXT: [[TMP1:%.*]] = load i8, i8* [[A1]], align 1
; CHECK-NEXT: ret void
;
%a = alloca [2 x i8]
%a0 = getelementptr [2 x i8], [2 x i8]* %a, i32 0, i32 0
%a1 = getelementptr [2 x i8], [2 x i8]* %a, i32 0, i32 1
store i8 1, i8* %a0
br i1 %c, label %if, label %else
if:
store [2 x i8] zeroinitializer, [2 x i8]* %a
br label %else
else:
load i8, i8* %a1
ret void
}
; Variation on the previous test case, where only the store to %a0 is dead,
; but not the one to %a1. This tests for a potential caching bug.
define void @test4(i1 %c) {
; CHECK-LABEL: @test4(
; CHECK-NEXT: [[A:%.*]] = alloca [2 x i8], align 1
; CHECK-NEXT: [[A1:%.*]] = getelementptr [2 x i8], [2 x i8]* [[A]], i32 0, i32 1
; CHECK-NEXT: store i8 1, i8* [[A1]], align 1
; CHECK-NEXT: br i1 [[C:%.*]], label [[IF:%.*]], label [[ELSE:%.*]]
; CHECK: if:
; CHECK-NEXT: store [2 x i8] zeroinitializer, [2 x i8]* [[A]], align 1
; CHECK-NEXT: br label [[ELSE]]
; CHECK: else:
; CHECK-NEXT: [[TMP1:%.*]] = load i8, i8* [[A1]], align 1
; CHECK-NEXT: ret void
;
%a = alloca [2 x i8]
%a0 = getelementptr [2 x i8], [2 x i8]* %a, i32 0, i32 0
%a1 = getelementptr [2 x i8], [2 x i8]* %a, i32 0, i32 1
store i8 1, i8* %a1
store i8 1, i8* %a0
br i1 %c, label %if, label %else
if:
store [2 x i8] zeroinitializer, [2 x i8]* %a
br label %else
else:
load i8, i8* %a1
ret void
}