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; RUN: opt < %s -basic-aa -dse -enable-dse-memoryssa -S | FileCheck %s
; RUN: opt < %s -aa-pipeline=basic-aa -passes=dse -enable-dse-memoryssa -S | FileCheck %s
target datalayout = "E-p:64:64:64-a0:0:8-f32:32:32-f64:64:64-i1:8:8-i8:8:8-i16:16:16-i32:32:32-i64:32:64-v64:64:64-v128:128:128"
declare void @llvm.memset.p0i8.i64(i8* nocapture, i8, i64, i1) nounwind
declare void @llvm.memset.element.unordered.atomic.p0i8.i64(i8* nocapture, i8, i64, i32) nounwind
declare void @llvm.memcpy.p0i8.p0i8.i64(i8* nocapture, i8* nocapture, i64, i1) nounwind
declare void @llvm.memcpy.element.unordered.atomic.p0i8.p0i8.i64(i8* nocapture, i8* nocapture, i64, i32) nounwind
declare void @llvm.init.trampoline(i8*, i8*, i8*)
; **** Noop load->store tests **************************************************
; We CAN optimize volatile loads.
define void @test_load_volatile(i32* %Q) {
; CHECK-LABEL: @test_load_volatile(
; CHECK-NEXT: [[A:%.*]] = load volatile i32, i32* [[Q:%.*]]
; CHECK-NEXT: store i32 [[A]], i32* [[Q]]
; CHECK-NEXT: ret void
;
%a = load volatile i32, i32* %Q
store i32 %a, i32* %Q
ret void
}
; We can NOT optimize volatile stores.
define void @test_store_volatile(i32* %Q) {
; CHECK-LABEL: @test_store_volatile(
; CHECK-NEXT: [[A:%.*]] = load i32, i32* [[Q:%.*]]
; CHECK-NEXT: store volatile i32 [[A]]
; CHECK-NEXT: ret void
;
%a = load i32, i32* %Q
store volatile i32 %a, i32* %Q
ret void
}
; PR2599 - load -> store to same address.
define void @test12({ i32, i32 }* %x) nounwind {
; CHECK-LABEL: @test12(
; CHECK-NEXT: [[TMP7:%.*]] = getelementptr { i32, i32 }, { i32, i32 }* [[X:%.*]], i32 0, i32 1
; CHECK-NEXT: [[TMP8:%.*]] = load i32, i32* [[TMP7]], align 4
; CHECK-NEXT: [[TMP17:%.*]] = sub i32 0, [[TMP8]]
; CHECK-NEXT: store i32 [[TMP17]], i32* [[TMP7]], align 4
; CHECK-NEXT: ret void
;
%tmp4 = getelementptr { i32, i32 }, { i32, i32 }* %x, i32 0, i32 0
%tmp5 = load i32, i32* %tmp4, align 4
%tmp7 = getelementptr { i32, i32 }, { i32, i32 }* %x, i32 0, i32 1
%tmp8 = load i32, i32* %tmp7, align 4
%tmp17 = sub i32 0, %tmp8
store i32 %tmp5, i32* %tmp4, align 4
store i32 %tmp17, i32* %tmp7, align 4
ret void
}
; Remove redundant store if loaded value is in another block.
define i32 @test26(i1 %c, i32* %p) {
; CHECK-LABEL: @test26(
; CHECK-NEXT: entry:
; CHECK-NEXT: br i1 [[C:%.*]], label [[BB1:%.*]], label [[BB2:%.*]]
; CHECK: bb1:
; CHECK-NEXT: br label [[BB3:%.*]]
; CHECK: bb2:
; CHECK-NEXT: br label [[BB3]]
; CHECK: bb3:
; CHECK-NEXT: ret i32 0
;
entry:
%v = load i32, i32* %p, align 4
br i1 %c, label %bb1, label %bb2
bb1:
br label %bb3
bb2:
store i32 %v, i32* %p, align 4
br label %bb3
bb3:
ret i32 0
}
; Remove redundant store if loaded value is in another block.
define i32 @test27(i1 %c, i32* %p) {
; CHECK-LABEL: @test27(
; CHECK-NEXT: entry:
; CHECK-NEXT: br i1 [[C:%.*]], label [[BB1:%.*]], label [[BB2:%.*]]
; CHECK: bb1:
; CHECK-NEXT: br label [[BB3:%.*]]
; CHECK: bb2:
; CHECK-NEXT: br label [[BB3]]
; CHECK: bb3:
; CHECK-NEXT: ret i32 0
;
entry:
%v = load i32, i32* %p, align 4
br i1 %c, label %bb1, label %bb2
bb1:
br label %bb3
bb2:
br label %bb3
bb3:
store i32 %v, i32* %p, align 4
ret i32 0
}
declare void @unknown_func()
; Remove redundant store, which is in the lame loop as the load.
define i32 @test33(i1 %c, i32* %p, i32 %i) {
; CHECK-LABEL: @test33(
; CHECK-NEXT: entry:
; CHECK-NEXT: br label [[BB1:%.*]]
; CHECK: bb1:
; CHECK-NEXT: br label [[BB2:%.*]]
; CHECK: bb2:
; CHECK-NEXT: call void @unknown_func()
; CHECK-NEXT: br i1 undef, label [[BB1]], label [[BB3:%.*]]
; CHECK: bb3:
; CHECK-NEXT: ret i32 0
;
entry:
br label %bb1
bb1:
%v = load i32, i32* %p, align 4
br label %bb2
bb2:
store i32 %v, i32* %p, align 4
; Might read and overwrite value at %p, but doesn't matter.
call void @unknown_func()
br i1 undef, label %bb1, label %bb3
bb3:
ret i32 0
}
declare void @unkown_write(i32*)
; We can't remove the "noop" store around an unkown write.
define void @test43(i32* %Q) {
; CHECK-LABEL: @test43(
; CHECK-NEXT: load
; CHECK-NEXT: call
; CHECK-NEXT: store
; CHECK-NEXT: ret void
;
%a = load i32, i32* %Q
call void @unkown_write(i32* %Q)
store i32 %a, i32* %Q
ret void
}
; We CAN remove it when the unkown write comes AFTER.
define void @test44(i32* %Q) {
; CHECK-LABEL: @test44(
; CHECK-NEXT: call
; CHECK-NEXT: ret void
%a = load i32, i32* %Q
store i32 %a, i32* %Q
call void @unkown_write(i32* %Q)
ret void
}
define void @test45(i32* %Q) {
; CHECK-LABEL: @test45(
; CHECK-NEXT: [[A:%.*]] = load
; CHECK-NEXT: store i32 [[A]]
; CHECK-NEXT: ret void
%a = load i32, i32* %Q
store i32 10, i32* %Q
store i32 %a, i32* %Q
ret void
}
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