; NOTE: Assertions have been autogenerated by utils/update_test_checks.py ; RUN: opt < %s -S -early-cse -earlycse-debug-hash | FileCheck %s ; RUN: opt < %s -S -basic-aa -early-cse-memssa | FileCheck %s ; RUN: opt < %s -S -passes=early-cse | FileCheck %s declare void @llvm.assume(i1) nounwind define void @test1(i8 %V, ptr%P) { ; CHECK-LABEL: @test1( ; CHECK-NEXT: store i32 23, ptr [[P:%.*]], align 4 ; CHECK-NEXT: [[C:%.*]] = zext i8 [[V:%.*]] to i32 ; CHECK-NEXT: store volatile i32 [[C]], ptr [[P]], align 4 ; CHECK-NEXT: store volatile i32 [[C]], ptr [[P]], align 4 ; CHECK-NEXT: [[E:%.*]] = add i32 [[C]], [[C]] ; CHECK-NEXT: store volatile i32 [[E]], ptr [[P]], align 4 ; CHECK-NEXT: store volatile i32 [[E]], ptr [[P]], align 4 ; CHECK-NEXT: store volatile i32 [[E]], ptr [[P]], align 4 ; CHECK-NEXT: ret void ; %A = bitcast i64 42 to double ;; dead %B = add i32 4, 19 ;; constant folds store i32 %B, ptr %P %C = zext i8 %V to i32 %D = zext i8 %V to i32 ;; CSE store volatile i32 %C, ptr %P store volatile i32 %D, ptr %P %E = add i32 %C, %C %F = add i32 %C, %C store volatile i32 %E, ptr %P store volatile i32 %F, ptr %P %G = add nuw i32 %C, %C store volatile i32 %G, ptr %P ret void } ;; Simple load value numbering. define i32 @test2(ptr%P) { ; CHECK-LABEL: @test2( ; CHECK-NEXT: [[V1:%.*]] = load i32, ptr [[P:%.*]], align 4 ; CHECK-NEXT: ret i32 0 ; %V1 = load i32, ptr %P %V2 = load i32, ptr %P %Diff = sub i32 %V1, %V2 ret i32 %Diff } define i32 @test2a(ptr%P, i1 %b) { ; CHECK-LABEL: @test2a( ; CHECK-NEXT: [[V1:%.*]] = load i32, ptr [[P:%.*]], align 4 ; CHECK-NEXT: tail call void @llvm.assume(i1 [[B:%.*]]) ; CHECK-NEXT: ret i32 0 ; %V1 = load i32, ptr %P tail call void @llvm.assume(i1 %b) %V2 = load i32, ptr %P %Diff = sub i32 %V1, %V2 ret i32 %Diff } ;; Cross block load value numbering. define i32 @test3(ptr%P, i1 %Cond) { ; CHECK-LABEL: @test3( ; CHECK-NEXT: [[V1:%.*]] = load i32, ptr [[P:%.*]], align 4 ; CHECK-NEXT: br i1 [[COND:%.*]], label [[T:%.*]], label [[F:%.*]] ; CHECK: T: ; CHECK-NEXT: store i32 4, ptr [[P]], align 4 ; CHECK-NEXT: ret i32 42 ; CHECK: F: ; CHECK-NEXT: ret i32 0 ; %V1 = load i32, ptr %P br i1 %Cond, label %T, label %F T: store i32 4, ptr %P ret i32 42 F: %V2 = load i32, ptr %P %Diff = sub i32 %V1, %V2 ret i32 %Diff } define i32 @test3a(ptr%P, i1 %Cond, i1 %b) { ; CHECK-LABEL: @test3a( ; CHECK-NEXT: [[V1:%.*]] = load i32, ptr [[P:%.*]], align 4 ; CHECK-NEXT: br i1 [[COND:%.*]], label [[T:%.*]], label [[F:%.*]] ; CHECK: T: ; CHECK-NEXT: store i32 4, ptr [[P]], align 4 ; CHECK-NEXT: ret i32 42 ; CHECK: F: ; CHECK-NEXT: tail call void @llvm.assume(i1 [[B:%.*]]) ; CHECK-NEXT: ret i32 0 ; %V1 = load i32, ptr %P br i1 %Cond, label %T, label %F T: store i32 4, ptr %P ret i32 42 F: tail call void @llvm.assume(i1 %b) %V2 = load i32, ptr %P %Diff = sub i32 %V1, %V2 ret i32 %Diff } ;; Cross block load value numbering stops when stores happen. define i32 @test4(ptr%P, i1 %Cond) { ; CHECK-LABEL: @test4( ; CHECK-NEXT: [[V1:%.*]] = load i32, ptr [[P:%.*]], align 4 ; CHECK-NEXT: br i1 [[COND:%.*]], label [[T:%.*]], label [[F:%.*]] ; CHECK: T: ; CHECK-NEXT: ret i32 42 ; CHECK: F: ; CHECK-NEXT: store i32 42, ptr [[P]], align 4 ; CHECK-NEXT: [[DIFF:%.*]] = sub i32 [[V1]], 42 ; CHECK-NEXT: ret i32 [[DIFF]] ; %V1 = load i32, ptr %P br i1 %Cond, label %T, label %F T: ret i32 42 F: ; Clobbers V1 store i32 42, ptr %P %V2 = load i32, ptr %P %Diff = sub i32 %V1, %V2 ret i32 %Diff } declare i32 @func(ptr%P) readonly ;; Simple call CSE'ing. define i32 @test5(ptr%P) { ; CHECK-LABEL: @test5( ; CHECK-NEXT: [[V1:%.*]] = call i32 @func(ptr [[P:%.*]]) ; CHECK-NEXT: ret i32 0 ; %V1 = call i32 @func(ptr %P) %V2 = call i32 @func(ptr %P) %Diff = sub i32 %V1, %V2 ret i32 %Diff } ;; Trivial Store->load forwarding define i32 @test6(ptr%P) { ; CHECK-LABEL: @test6( ; CHECK-NEXT: store i32 42, ptr [[P:%.*]], align 4 ; CHECK-NEXT: ret i32 42 ; store i32 42, ptr %P %V1 = load i32, ptr %P ret i32 %V1 } define i32 @test6a(ptr%P, i1 %b) { ; CHECK-LABEL: @test6a( ; CHECK-NEXT: store i32 42, ptr [[P:%.*]], align 4 ; CHECK-NEXT: tail call void @llvm.assume(i1 [[B:%.*]]) ; CHECK-NEXT: ret i32 42 ; store i32 42, ptr %P tail call void @llvm.assume(i1 %b) %V1 = load i32, ptr %P ret i32 %V1 } ;; Trivial dead store elimination. define void @test7(ptr%P) { ; CHECK-LABEL: @test7( ; CHECK-NEXT: store i32 45, ptr [[P:%.*]], align 4 ; CHECK-NEXT: ret void ; store i32 42, ptr %P store i32 45, ptr %P ret void } ;; Readnone functions aren't invalidated by stores. define i32 @test8(ptr%P) { ; CHECK-LABEL: @test8( ; CHECK-NEXT: [[V1:%.*]] = call i32 @func(ptr [[P:%.*]]) #[[ATTR2:[0-9]+]] ; CHECK-NEXT: store i32 4, ptr [[P]], align 4 ; CHECK-NEXT: ret i32 0 ; %V1 = call i32 @func(ptr %P) readnone store i32 4, ptr %P %V2 = call i32 @func(ptr %P) readnone %Diff = sub i32 %V1, %V2 ret i32 %Diff } ;; Trivial DSE can't be performed across a readonly call. The call ;; can observe the earlier write. define i32 @test9(ptr%P) { ; CHECK-LABEL: @test9( ; CHECK-NEXT: store i32 4, ptr [[P:%.*]], align 4 ; CHECK-NEXT: [[V1:%.*]] = call i32 @func(ptr [[P]]) #[[ATTR1:[0-9]+]] ; CHECK-NEXT: store i32 5, ptr [[P]], align 4 ; CHECK-NEXT: ret i32 [[V1]] ; store i32 4, ptr %P %V1 = call i32 @func(ptr %P) readonly store i32 5, ptr %P ret i32 %V1 } ;; Trivial DSE can be performed across a readnone call. define i32 @test10(ptr%P) { ; CHECK-LABEL: @test10( ; CHECK-NEXT: [[V1:%.*]] = call i32 @func(ptr [[P:%.*]]) #[[ATTR2]] ; CHECK-NEXT: store i32 5, ptr [[P]], align 4 ; CHECK-NEXT: ret i32 [[V1]] ; store i32 4, ptr %P %V1 = call i32 @func(ptr %P) readnone store i32 5, ptr %P ret i32 %V1 } ;; Trivial dead store elimination - should work for an entire series of dead stores too. define void @test11(ptr%P) { ; CHECK-LABEL: @test11( ; CHECK-NEXT: store i32 45, ptr [[P:%.*]], align 4 ; CHECK-NEXT: ret void ; store i32 42, ptr %P store i32 43, ptr %P store i32 44, ptr %P store i32 45, ptr %P ret void } define i32 @test12(i1 %B, ptr %P1, ptr %P2) { ; CHECK-LABEL: @test12( ; CHECK-NEXT: [[LOAD0:%.*]] = load i32, ptr [[P1:%.*]], align 4 ; CHECK-NEXT: [[TMP1:%.*]] = load atomic i32, ptr [[P2:%.*]] seq_cst, align 4 ; CHECK-NEXT: [[LOAD1:%.*]] = load i32, ptr [[P1]], align 4 ; CHECK-NEXT: [[SEL:%.*]] = select i1 [[B:%.*]], i32 [[LOAD0]], i32 [[LOAD1]] ; CHECK-NEXT: ret i32 [[SEL]] ; %load0 = load i32, ptr %P1 %1 = load atomic i32, ptr %P2 seq_cst, align 4 %load1 = load i32, ptr %P1 %sel = select i1 %B, i32 %load0, i32 %load1 ret i32 %sel } define void @dse1(ptr%P) { ; CHECK-LABEL: @dse1( ; CHECK-NEXT: [[V:%.*]] = load i32, ptr [[P:%.*]], align 4 ; CHECK-NEXT: ret void ; %v = load i32, ptr %P store i32 %v, ptr %P ret void } define void @dse2(ptr%P) { ; CHECK-LABEL: @dse2( ; CHECK-NEXT: [[V:%.*]] = load atomic i32, ptr [[P:%.*]] seq_cst, align 4 ; CHECK-NEXT: ret void ; %v = load atomic i32, ptr %P seq_cst, align 4 store i32 %v, ptr %P ret void } define void @dse3(ptr%P) { ; CHECK-LABEL: @dse3( ; CHECK-NEXT: [[V:%.*]] = load atomic i32, ptr [[P:%.*]] seq_cst, align 4 ; CHECK-NEXT: ret void ; %v = load atomic i32, ptr %P seq_cst, align 4 store atomic i32 %v, ptr %P unordered, align 4 ret void } define i32 @dse4(ptr%P, ptr%Q) { ; CHECK-LABEL: @dse4( ; CHECK-NEXT: [[A:%.*]] = load i32, ptr [[Q:%.*]], align 4 ; CHECK-NEXT: [[V:%.*]] = load atomic i32, ptr [[P:%.*]] unordered, align 4 ; CHECK-NEXT: ret i32 0 ; %a = load i32, ptr %Q %v = load atomic i32, ptr %P unordered, align 4 store atomic i32 %v, ptr %P unordered, align 4 %b = load i32, ptr %Q %res = sub i32 %a, %b ret i32 %res } ; Note that in this example, %P and %Q could in fact be the same ; pointer. %v could be different than the value observed for %a ; and that's okay because we're using relaxed memory ordering. ; The only guarantee we have to provide is that each of the loads ; has to observe some value written to that location. We do ; not have to respect the order in which those writes were done. define i32 @dse5(ptr%P, ptr%Q) { ; CHECK-LABEL: @dse5( ; CHECK-NEXT: [[V:%.*]] = load atomic i32, ptr [[P:%.*]] unordered, align 4 ; CHECK-NEXT: [[A:%.*]] = load atomic i32, ptr [[Q:%.*]] unordered, align 4 ; CHECK-NEXT: ret i32 0 ; %v = load atomic i32, ptr %P unordered, align 4 %a = load atomic i32, ptr %Q unordered, align 4 store atomic i32 %v, ptr %P unordered, align 4 %b = load atomic i32, ptr %Q unordered, align 4 %res = sub i32 %a, %b ret i32 %res } define void @dse_neg1(ptr%P) { ; CHECK-LABEL: @dse_neg1( ; CHECK-NEXT: store i32 5, ptr [[P:%.*]], align 4 ; CHECK-NEXT: ret void ; %v = load i32, ptr %P store i32 5, ptr %P ret void } ; Could remove the store, but only if ordering was somehow ; encoded. define void @dse_neg2(ptr%P) { ; CHECK-LABEL: @dse_neg2( ; CHECK-NEXT: [[V:%.*]] = load i32, ptr [[P:%.*]], align 4 ; CHECK-NEXT: store atomic i32 [[V]], ptr [[P]] seq_cst, align 4 ; CHECK-NEXT: ret void ; %v = load i32, ptr %P store atomic i32 %v, ptr %P seq_cst, align 4 ret void } @c = external global i32, align 4 declare i32 @reads_c(i32 returned) define void @pr28763() { ; CHECK-LABEL: @pr28763( ; CHECK-NEXT: entry: ; CHECK-NEXT: store i32 0, ptr @c, align 4 ; CHECK-NEXT: [[CALL:%.*]] = call i32 @reads_c(i32 0) ; CHECK-NEXT: store i32 2, ptr @c, align 4 ; CHECK-NEXT: ret void ; entry: %load = load i32, ptr @c, align 4 store i32 0, ptr @c, align 4 %call = call i32 @reads_c(i32 0) store i32 2, ptr @c, align 4 ret void } define i1 @cse_freeze(i1 %a) { ; CHECK-LABEL: @cse_freeze( ; CHECK-NEXT: entry: ; CHECK-NEXT: [[B:%.*]] = freeze i1 [[A:%.*]] ; CHECK-NEXT: ret i1 [[B]] ; entry: %b = freeze i1 %a %c = freeze i1 %a %and = and i1 %b, %c ret i1 %and }