; NOTE: Assertions have been autogenerated by utils/update_test_checks.py ; RUN: opt -passes=dse -dse-optimize-memoryssa=false -S %s | FileCheck --check-prefixes=CHECK,UNOPT %s ; RUN: opt -passes=dse -dse-optimize-memoryssa -S %s | FileCheck --check-prefixes=CHECK,OPT %s ; RUN: opt -passes=dse -S %s | FileCheck --check-prefixes=CHECK,OPT %s target datalayout = "e-p:64:64:64-i1:8:8-i8:8:8-i16:16:16-i32:32:32-i64:64:64-f32:32:32-f64:64:64-v64:64:64-v128:128:128-a0:0:64-s0:64:64-f80:128:128-n8:16:32:64-S128" @a = external global [32 x i8], align 16 declare void @llvm.memcpy.p0.p0.i64(ptr noalias nocapture writeonly, ptr noalias nocapture readonly, i64, i1 immarg) ; Test case for PR16520. The store in %if.then is redundant, because the same value ; has been stored earlier to the same location. define void @test1_pr16520(i1 %b, ptr nocapture %r) { ; CHECK-LABEL: @test1_pr16520( ; CHECK-NEXT: entry: ; CHECK-NEXT: store i8 1, ptr [[R:%.*]], align 1 ; CHECK-NEXT: br i1 [[B:%.*]], label [[IF_THEN:%.*]], label [[IF_ELSE:%.*]] ; CHECK: if.then: ; CHECK-NEXT: tail call void @fn_mayread_or_clobber() ; CHECK-NEXT: br label [[IF_END:%.*]] ; CHECK: if.else: ; CHECK-NEXT: tail call void @fn_mayread_or_clobber() ; CHECK-NEXT: br label [[IF_END]] ; CHECK: if.end: ; CHECK-NEXT: ret void ; entry: store i8 1, ptr %r, align 1 br i1 %b, label %if.then, label %if.else if.then: ; preds = %entry store i8 1, ptr %r, align 1 tail call void @fn_mayread_or_clobber() br label %if.end if.else: ; preds = %entry tail call void @fn_mayread_or_clobber() br label %if.end if.end: ; preds = %if.else, %if.then ret void } declare void @fn_mayread_or_clobber() declare void @fn_readonly() readonly define void @test2(i1 %b, ptr nocapture %r) { ; CHECK-LABEL: @test2( ; CHECK-NEXT: entry: ; CHECK-NEXT: store i8 1, ptr [[R:%.*]], align 1 ; CHECK-NEXT: br i1 [[B:%.*]], label [[IF_THEN:%.*]], label [[IF_ELSE:%.*]] ; CHECK: if.then: ; CHECK-NEXT: tail call void @fn_readonly() ; CHECK-NEXT: br label [[IF_END:%.*]] ; CHECK: if.else: ; CHECK-NEXT: tail call void @fn_readonly() ; CHECK-NEXT: br label [[IF_END]] ; CHECK: if.end: ; CHECK-NEXT: ret void ; entry: store i8 1, ptr %r, align 1 br i1 %b, label %if.then, label %if.else if.then: ; preds = %entry tail call void @fn_readonly() br label %if.end if.else: ; preds = %entry tail call void @fn_readonly() br label %if.end if.end: ; preds = %if.else, %if.then store i8 1, ptr %r, align 1 ret void } ; Make sure volatile stores are not removed. define void @test2_volatile(i1 %b, ptr nocapture %r) { ; CHECK-LABEL: @test2_volatile( ; CHECK-NEXT: entry: ; CHECK-NEXT: store volatile i8 1, ptr [[R:%.*]], align 1 ; CHECK-NEXT: br i1 [[B:%.*]], label [[IF_THEN:%.*]], label [[IF_ELSE:%.*]] ; CHECK: if.then: ; CHECK-NEXT: tail call void @fn_readonly() ; CHECK-NEXT: br label [[IF_END:%.*]] ; CHECK: if.else: ; CHECK-NEXT: tail call void @fn_readonly() ; CHECK-NEXT: br label [[IF_END]] ; CHECK: if.end: ; CHECK-NEXT: store volatile i8 1, ptr [[R]], align 1 ; CHECK-NEXT: ret void ; entry: store volatile i8 1, ptr %r, align 1 br i1 %b, label %if.then, label %if.else if.then: ; preds = %entry tail call void @fn_readonly() br label %if.end if.else: ; preds = %entry tail call void @fn_readonly() br label %if.end if.end: ; preds = %if.else, %if.then store volatile i8 1, ptr %r, align 1 ret void } define void @test3(i1 %b, ptr nocapture %r) { ; CHECK-LABEL: @test3( ; CHECK-NEXT: entry: ; CHECK-NEXT: store i8 1, ptr [[R:%.*]], align 1 ; CHECK-NEXT: br i1 [[B:%.*]], label [[IF_THEN:%.*]], label [[IF_ELSE:%.*]] ; CHECK: if.then: ; CHECK-NEXT: tail call void @fn_mayread_or_clobber() ; CHECK-NEXT: br label [[IF_END:%.*]] ; CHECK: if.else: ; CHECK-NEXT: tail call void @fn_readonly() ; CHECK-NEXT: br label [[IF_END]] ; CHECK: if.end: ; CHECK-NEXT: store i8 1, ptr [[R]], align 1 ; CHECK-NEXT: ret void ; entry: store i8 1, ptr %r, align 1 br i1 %b, label %if.then, label %if.else if.then: ; preds = %entry tail call void @fn_mayread_or_clobber() br label %if.end if.else: ; preds = %entry tail call void @fn_readonly() br label %if.end if.end: ; preds = %if.else, %if.then store i8 1, ptr %r, align 1 ret void } define void @test4(i1 %b, ptr nocapture %r) { ; CHECK-LABEL: @test4( ; CHECK-NEXT: entry: ; CHECK-NEXT: store i8 1, ptr [[R:%.*]], align 1 ; CHECK-NEXT: br i1 [[B:%.*]], label [[IF_THEN:%.*]], label [[IF_ELSE:%.*]] ; CHECK: if.then: ; CHECK-NEXT: tail call void @fn_readonly() ; CHECK-NEXT: br label [[IF_END:%.*]] ; CHECK: if.else: ; CHECK-NEXT: tail call void @fn_mayread_or_clobber() ; CHECK-NEXT: br label [[IF_END]] ; CHECK: if.end: ; CHECK-NEXT: store i8 1, ptr [[R]], align 1 ; CHECK-NEXT: ret void ; entry: store i8 1, ptr %r, align 1 br i1 %b, label %if.then, label %if.else if.then: ; preds = %entry tail call void @fn_readonly() br label %if.end if.else: ; preds = %entry tail call void @fn_mayread_or_clobber() br label %if.end if.end: ; preds = %if.else, %if.then store i8 1, ptr %r, align 1 ret void } define void @test5(i1 %b, ptr nocapture %r) { ; CHECK-LABEL: @test5( ; CHECK-NEXT: entry: ; CHECK-NEXT: store i8 1, ptr [[R:%.*]], align 1 ; CHECK-NEXT: br i1 [[B:%.*]], label [[IF_THEN:%.*]], label [[IF_ELSE:%.*]] ; CHECK: if.then: ; CHECK-NEXT: tail call void @fn_readonly() ; CHECK-NEXT: br label [[IF_END:%.*]] ; CHECK: if.else: ; CHECK-NEXT: tail call void @fn_mayread_or_clobber() ; CHECK-NEXT: br label [[IF_END]] ; CHECK: if.end: ; CHECK-NEXT: store i8 1, ptr [[R]], align 1 ; CHECK-NEXT: ret void ; entry: store i8 1, ptr %r, align 1 br i1 %b, label %if.then, label %if.else if.then: ; preds = %entry tail call void @fn_readonly() br label %if.end if.else: ; preds = %entry tail call void @fn_mayread_or_clobber() br label %if.end if.end: ; preds = %if.else, %if.then store i8 1, ptr %r, align 1 ret void } declare i1 @cond() readnone define void @test6(ptr noalias %P) { ; CHECK-LABEL: @test6( ; CHECK-NEXT: entry: ; CHECK-NEXT: br label [[FOR_HEADER:%.*]] ; CHECK: for.header: ; CHECK-NEXT: store i32 1, ptr [[P:%.*]], align 4 ; CHECK-NEXT: [[C1:%.*]] = call i1 @cond() ; CHECK-NEXT: br i1 [[C1]], label [[FOR_BODY:%.*]], label [[END:%.*]] ; CHECK: for.body: ; CHECK-NEXT: [[LV:%.*]] = load i32, ptr [[P]], align 4 ; CHECK-NEXT: br label [[FOR_HEADER]] ; CHECK: end: ; CHECK-NEXT: store i32 3, ptr [[P]], align 4 ; CHECK-NEXT: ret void ; entry: br label %for.header for.header: store i32 1, ptr %P, align 4 %c1 = call i1 @cond() br i1 %c1, label %for.body, label %end for.body: store i32 1, ptr %P, align 4 %lv = load i32, ptr %P br label %for.header end: store i32 3, ptr %P, align 4 ret void } ; Make sure the store in %bb3 can be eliminated in the presences of early returns. define void @test7(ptr noalias %P) { ; CHECK-LABEL: @test7( ; CHECK-NEXT: store i32 0, ptr [[P:%.*]], align 4 ; CHECK-NEXT: br i1 true, label [[BB1:%.*]], label [[BB2:%.*]] ; CHECK: bb1: ; CHECK-NEXT: br label [[BB3:%.*]] ; CHECK: bb2: ; CHECK-NEXT: ret void ; CHECK: bb3: ; CHECK-NEXT: ret void ; store i32 0, ptr %P br i1 true, label %bb1, label %bb2 bb1: br label %bb3 bb2: ret void bb3: store i32 0, ptr %P ret void } ; Make sure the store in %bb3 won't be eliminated because it may be clobbered before. define void @test8(ptr %P) { ; CHECK-LABEL: @test8( ; CHECK-NEXT: store i32 0, ptr [[P:%.*]], align 4 ; CHECK-NEXT: br i1 true, label [[BB1:%.*]], label [[BB2:%.*]] ; CHECK: bb1: ; CHECK-NEXT: call void @fn_mayread_or_clobber() ; CHECK-NEXT: br label [[BB3:%.*]] ; CHECK: bb2: ; CHECK-NEXT: ret void ; CHECK: bb3: ; CHECK-NEXT: store i32 0, ptr [[P]], align 4 ; CHECK-NEXT: ret void ; store i32 0, ptr %P br i1 true, label %bb1, label %bb2 bb1: call void @fn_mayread_or_clobber() br label %bb3 bb2: ret void bb3: store i32 0, ptr %P ret void } ; Make sure the store in %bb3 will be eliminated because only the early exit path ; may be clobbered. define void @test9(ptr noalias %P) { ; CHECK-LABEL: @test9( ; CHECK-NEXT: store i32 0, ptr [[P:%.*]], align 4 ; CHECK-NEXT: br i1 true, label [[BB1:%.*]], label [[BB2:%.*]] ; CHECK: bb1: ; CHECK-NEXT: br label [[BB3:%.*]] ; CHECK: bb2: ; CHECK-NEXT: call void @fn_mayread_or_clobber() ; CHECK-NEXT: ret void ; CHECK: bb3: ; CHECK-NEXT: ret void ; store i32 0, ptr %P br i1 true, label %bb1, label %bb2 bb1: br label %bb3 bb2: call void @fn_mayread_or_clobber() ret void bb3: store i32 0, ptr %P ret void } ; The store in bb3 can be eliminated, because the store in bb1 cannot alias it. define void @test10(ptr noalias %P, ptr %Q, i1 %c) { ; UNOPT-LABEL: @test10( ; UNOPT-NEXT: store i32 0, ptr [[P:%.*]], align 4 ; UNOPT-NEXT: br i1 [[C:%.*]], label [[BB1:%.*]], label [[BB2:%.*]] ; UNOPT: bb1: ; UNOPT-NEXT: store i32 10, ptr [[Q:%.*]], align 4 ; UNOPT-NEXT: br label [[BB3:%.*]] ; UNOPT: bb2: ; UNOPT-NEXT: ret void ; UNOPT: bb3: ; UNOPT-NEXT: store i32 0, ptr [[P]], align 4 ; UNOPT-NEXT: ret void ; ; OPT-LABEL: @test10( ; OPT-NEXT: store i32 0, ptr [[P:%.*]], align 4 ; OPT-NEXT: br i1 [[C:%.*]], label [[BB1:%.*]], label [[BB2:%.*]] ; OPT: bb1: ; OPT-NEXT: store i32 10, ptr [[Q:%.*]], align 4 ; OPT-NEXT: br label [[BB3:%.*]] ; OPT: bb2: ; OPT-NEXT: ret void ; OPT: bb3: ; OPT-NEXT: ret void ; store i32 0, ptr %P br i1 %c, label %bb1, label %bb2 bb1: store i32 10, ptr %Q br label %bb3 bb2: ret void bb3: store i32 0, ptr %P ret void } define void @test11_smaller_later_store(ptr noalias %P, ptr %Q, i1 %c) { ; CHECK-LABEL: @test11_smaller_later_store( ; CHECK-NEXT: store i32 0, ptr [[P:%.*]], align 4 ; CHECK-NEXT: br i1 [[C:%.*]], label [[BB1:%.*]], label [[BB2:%.*]] ; CHECK: bb1: ; CHECK-NEXT: br label [[BB3:%.*]] ; CHECK: bb2: ; CHECK-NEXT: ret void ; CHECK: bb3: ; CHECK-NEXT: store i8 0, ptr [[P]], align 1 ; CHECK-NEXT: ret void ; store i32 0, ptr %P br i1 %c, label %bb1, label %bb2 bb1: br label %bb3 bb2: ret void bb3: store i8 0, ptr %P ret void } define void @test11_smaller_earlier_store(ptr noalias %P, ptr %Q, i1 %c) { ; CHECK-LABEL: @test11_smaller_earlier_store( ; CHECK-NEXT: store i8 0, ptr [[P:%.*]], align 1 ; CHECK-NEXT: br i1 [[C:%.*]], label [[BB1:%.*]], label [[BB2:%.*]] ; CHECK: bb1: ; CHECK-NEXT: br label [[BB3:%.*]] ; CHECK: bb2: ; CHECK-NEXT: ret void ; CHECK: bb3: ; CHECK-NEXT: store i32 0, ptr [[P]], align 4 ; CHECK-NEXT: ret void ; store i8 0, ptr %P br i1 %c, label %bb1, label %bb2 bb1: br label %bb3 bb2: ret void bb3: store i32 0, ptr %P ret void } declare void @llvm.memset.p0.i64(ptr nocapture writeonly, i8, i64, i1 immarg) #1 define void @test12_memset_simple(ptr %ptr) { ; CHECK-LABEL: @test12_memset_simple( ; CHECK-NEXT: call void @llvm.memset.p0.i64(ptr [[PTR:%.*]], i8 0, i64 10, i1 false) ; CHECK-NEXT: ret void ; call void @llvm.memset.p0.i64(ptr %ptr, i8 0, i64 10, i1 false) %ptr.5 = getelementptr i8, ptr %ptr, i64 4 store i8 0, ptr %ptr.5 ret void } define void @test12_memset_other_store_in_between(ptr %ptr) { ; UNOPT-LABEL: @test12_memset_other_store_in_between( ; UNOPT-NEXT: call void @llvm.memset.p0.i64(ptr [[PTR:%.*]], i8 0, i64 10, i1 false) ; UNOPT-NEXT: [[PTR_4:%.*]] = getelementptr i8, ptr [[PTR]], i64 4 ; UNOPT-NEXT: store i8 8, ptr [[PTR_4]], align 1 ; UNOPT-NEXT: [[PTR_5:%.*]] = getelementptr i8, ptr [[PTR]], i64 5 ; UNOPT-NEXT: store i8 0, ptr [[PTR_5]], align 1 ; UNOPT-NEXT: ret void ; ; OPT-LABEL: @test12_memset_other_store_in_between( ; OPT-NEXT: call void @llvm.memset.p0.i64(ptr [[PTR:%.*]], i8 0, i64 10, i1 false) ; OPT-NEXT: [[PTR_4:%.*]] = getelementptr i8, ptr [[PTR]], i64 4 ; OPT-NEXT: store i8 8, ptr [[PTR_4]], align 1 ; OPT-NEXT: ret void ; call void @llvm.memset.p0.i64(ptr %ptr, i8 0, i64 10, i1 false) %ptr.4 = getelementptr i8, ptr %ptr, i64 4 store i8 8, ptr %ptr.4 %ptr.5 = getelementptr i8, ptr %ptr, i64 5 store i8 0, ptr %ptr.5 ret void } declare ptr @__memset_chk(ptr writeonly, i32, i64, i64) argmemonly writeonly nofree nounwind define void @test12_memset_chk_other_store_in_between(ptr %ptr) { ; CHECK-LABEL: @test12_memset_chk_other_store_in_between( ; CHECK-NEXT: [[CALL:%.*]] = tail call ptr @__memset_chk(ptr [[PTR:%.*]], i32 0, i64 10, i64 -1) ; CHECK-NEXT: [[PTR_4:%.*]] = getelementptr i8, ptr [[PTR]], i64 4 ; CHECK-NEXT: store i8 8, ptr [[PTR_4]], align 1 ; CHECK-NEXT: [[PTR_5:%.*]] = getelementptr i8, ptr [[PTR]], i64 5 ; CHECK-NEXT: store i8 0, ptr [[PTR_5]], align 1 ; CHECK-NEXT: ret void ; %call = tail call ptr @__memset_chk(ptr %ptr, i32 0, i64 10, i64 -1) %ptr.4 = getelementptr i8, ptr %ptr, i64 4 store i8 8, ptr %ptr.4 %ptr.5 = getelementptr i8, ptr %ptr, i64 5 store i8 0, ptr %ptr.5 ret void } declare void @use(ptr) define void @test12_memset_chk_other_store_in_between_stack_obj_escape_after(i64 %n) { ; CHECK-LABEL: @test12_memset_chk_other_store_in_between_stack_obj_escape_after( ; CHECK-NEXT: [[OBJ:%.*]] = alloca [200 x i8], align 1 ; CHECK-NEXT: [[CALL:%.*]] = tail call ptr @__memset_chk(ptr [[OBJ]], i32 0, i64 10, i64 [[N:%.*]]) ; CHECK-NEXT: [[PTR_4:%.*]] = getelementptr i8, ptr [[OBJ]], i64 4 ; CHECK-NEXT: store i8 8, ptr [[PTR_4]], align 1 ; CHECK-NEXT: [[PTR_5:%.*]] = getelementptr i8, ptr [[OBJ]], i64 5 ; CHECK-NEXT: store i8 0, ptr [[PTR_5]], align 1 ; CHECK-NEXT: call void @use(ptr [[OBJ]]) ; CHECK-NEXT: ret void ; %obj = alloca [200 x i8] %call = tail call ptr @__memset_chk(ptr %obj, i32 0, i64 10, i64 %n) %ptr.4 = getelementptr i8, ptr %obj, i64 4 store i8 8, ptr %ptr.4 %ptr.5 = getelementptr i8, ptr %obj, i64 5 store i8 0, ptr %ptr.5 call void @use(ptr %obj) ret void } define void @test12_memset_chk_other_store_in_between_stack_obj_escape_before(i64 %n) { ; CHECK-LABEL: @test12_memset_chk_other_store_in_between_stack_obj_escape_before( ; CHECK-NEXT: [[OBJ:%.*]] = alloca [200 x i8], align 1 ; CHECK-NEXT: call void @use(ptr [[OBJ]]) ; CHECK-NEXT: [[CALL:%.*]] = tail call ptr @__memset_chk(ptr [[OBJ]], i32 0, i64 10, i64 [[N:%.*]]) ; CHECK-NEXT: [[PTR_4:%.*]] = getelementptr i8, ptr [[OBJ]], i64 4 ; CHECK-NEXT: store i8 8, ptr [[PTR_4]], align 1 ; CHECK-NEXT: [[PTR_5:%.*]] = getelementptr i8, ptr [[OBJ]], i64 5 ; CHECK-NEXT: store i8 0, ptr [[PTR_5]], align 1 ; CHECK-NEXT: [[PTR_10:%.*]] = getelementptr i8, ptr [[OBJ]], i64 10 ; CHECK-NEXT: store i8 0, ptr [[PTR_10]], align 1 ; CHECK-NEXT: call void @use(ptr [[OBJ]]) ; CHECK-NEXT: ret void ; %obj = alloca [200 x i8] call void @use(ptr %obj) %call = tail call ptr @__memset_chk(ptr %obj, i32 0, i64 10, i64 %n) %ptr.4 = getelementptr i8, ptr %obj, i64 4 store i8 8, ptr %ptr.4 %ptr.5 = getelementptr i8, ptr %obj, i64 5 store i8 0, ptr %ptr.5 %ptr.10 = getelementptr i8, ptr %obj, i64 10 store i8 0, ptr %ptr.10 call void @use(ptr %obj) ret void } define void @test12_memset_other_store_in_between_partial_overlap(ptr %ptr) { ; CHECK-LABEL: @test12_memset_other_store_in_between_partial_overlap( ; CHECK-NEXT: call void @llvm.memset.p0.i64(ptr [[PTR:%.*]], i8 0, i64 10, i1 false) ; CHECK-NEXT: [[PTR_4:%.*]] = getelementptr i8, ptr [[PTR]], i64 4 ; CHECK-NEXT: store i16 8, ptr [[PTR_4]], align 2 ; CHECK-NEXT: [[PTR_5:%.*]] = getelementptr i8, ptr [[PTR]], i64 5 ; CHECK-NEXT: store i16 0, ptr [[PTR_5]], align 2 ; CHECK-NEXT: ret void ; call void @llvm.memset.p0.i64(ptr %ptr, i8 0, i64 10, i1 false) %ptr.4 = getelementptr i8, ptr %ptr, i64 4 store i16 8, ptr %ptr.4 %ptr.5 = getelementptr i8, ptr %ptr, i64 5 store i16 0, ptr %ptr.5 ret void } define void @test12_memset_later_store_exceeds_memset(ptr %ptr) { ; CHECK-LABEL: @test12_memset_later_store_exceeds_memset( ; CHECK-NEXT: call void @llvm.memset.p0.i64(ptr align 1 [[PTR:%.*]], i8 0, i64 8, i1 false) ; CHECK-NEXT: [[PTR_4:%.*]] = getelementptr i8, ptr [[PTR]], i64 4 ; CHECK-NEXT: store i8 8, ptr [[PTR_4]], align 1 ; CHECK-NEXT: [[PTR_5:%.*]] = getelementptr i8, ptr [[PTR]], i64 8 ; CHECK-NEXT: store i64 0, ptr [[PTR_5]], align 8 ; CHECK-NEXT: ret void ; call void @llvm.memset.p0.i64(ptr %ptr, i8 0, i64 10, i1 false) %ptr.4 = getelementptr i8, ptr %ptr, i64 4 store i8 8, ptr %ptr.4 %ptr.5 = getelementptr i8, ptr %ptr, i64 8 store i64 0, ptr %ptr.5 ret void } define void @test12_memset_later_store_before_memset(ptr %ptr) { ; CHECK-LABEL: @test12_memset_later_store_before_memset( ; CHECK-NEXT: [[PTR_1:%.*]] = getelementptr i8, ptr [[PTR:%.*]], i64 1 ; CHECK-NEXT: [[TMP1:%.*]] = getelementptr inbounds i8, ptr [[PTR_1]], i64 7 ; CHECK-NEXT: call void @llvm.memset.p0.i64(ptr align 1 [[TMP1]], i8 0, i64 3, i1 false) ; CHECK-NEXT: store i64 0, ptr [[PTR]], align 8 ; CHECK-NEXT: ret void ; %ptr.1 = getelementptr i8, ptr %ptr, i64 1 call void @llvm.memset.p0.i64(ptr %ptr.1, i8 0, i64 10, i1 false) %ptr.4 = getelementptr i8, ptr %ptr, i64 4 store i8 8, ptr %ptr.4 store i64 0, ptr %ptr ret void } ; The memset will be shortened and the store will not be redundant afterwards. ; It cannot be eliminated. define void @test13_memset_shortened(ptr %ptr) { ; CHECK-LABEL: @test13_memset_shortened( ; CHECK-NEXT: [[TMP1:%.*]] = getelementptr inbounds i8, ptr [[PTR:%.*]], i64 8 ; CHECK-NEXT: call void @llvm.memset.p0.i64(ptr align 1 [[TMP1]], i8 0, i64 16, i1 false) ; CHECK-NEXT: store i64 0, ptr [[PTR]], align 8 ; CHECK-NEXT: ret void ; call void @llvm.memset.p0.i64(ptr %ptr, i8 0, i64 24, i1 false) store i64 0, ptr %ptr ret void } declare ptr @strcat(ptr, ptr) nounwind argmemonly define void @test14_strcat(ptr noalias %P, ptr noalias %Q) { ; CHECK-LABEL: @test14_strcat( ; CHECK-NEXT: [[CALL1:%.*]] = call ptr @strcat(ptr [[P:%.*]], ptr [[Q:%.*]]) ; CHECK-NEXT: [[CALL2:%.*]] = call ptr @strcat(ptr [[P]], ptr [[Q]]) ; CHECK-NEXT: ret void ; %call1 = call ptr @strcat(ptr %P, ptr %Q) ; FIXME: Eliminate the second strcat as a "store of existing value" for this particular case, where both strcat's are identical (same source, not just same dest). %call2 = call ptr @strcat(ptr %P, ptr %Q) ret void } define void @pr49927(ptr %q, ptr %p) { ; CHECK-LABEL: @pr49927( ; CHECK-NEXT: [[V:%.*]] = load i32, ptr [[P:%.*]], align 4 ; CHECK-NEXT: store i32 [[V]], ptr [[Q:%.*]], align 4 ; CHECK-NEXT: store i32 [[V]], ptr [[P]], align 4 ; CHECK-NEXT: ret void ; %v = load i32, ptr %p, align 4 store i32 %v, ptr %q, align 4 store i32 %v, ptr %p, align 4 ret void } define void @pr50339(ptr nocapture readonly %0) { ; CHECK-LABEL: @pr50339( ; CHECK-NEXT: tail call void @llvm.memcpy.p0.p0.i64(ptr noundef nonnull align 16 dereferenceable(16) @a, ptr noundef nonnull align 1 dereferenceable(16) [[TMP0:%.*]], i64 16, i1 false) ; CHECK-NEXT: tail call void @llvm.memcpy.p0.p0.i64(ptr noundef nonnull align 16 dereferenceable(16) @a, ptr noundef nonnull align 1 dereferenceable(16) [[TMP0]], i64 16, i1 false) ; CHECK-NEXT: ret void ; tail call void @llvm.memcpy.p0.p0.i64(ptr noundef nonnull align 16 dereferenceable(16) @a, ptr noundef nonnull align 1 dereferenceable(16) %0, i64 16, i1 false) ; FIXME: Eliminate the second memcpy as a "store of existing value" for this particular case, where both memcpy's are identical (same source, not just same dest). tail call void @llvm.memcpy.p0.p0.i64(ptr noundef nonnull align 16 dereferenceable(16) @a, ptr noundef nonnull align 1 dereferenceable(16) %0, i64 16, i1 false) ret void } ; Cannot remove the second memcpy as redundant store, because %src is modified ; in between. define i8 @memset_optimized_access(ptr noalias %dst, ptr noalias %src) { ; CHECK-LABEL: @memset_optimized_access( ; CHECK-NEXT: tail call void @llvm.memcpy.p0.p0.i64(ptr [[DST:%.*]], ptr [[SRC:%.*]], i64 16, i1 false) ; CHECK-NEXT: store i8 99, ptr [[SRC]], align 1 ; CHECK-NEXT: [[L:%.*]] = load i8, ptr [[DST]], align 1 ; CHECK-NEXT: tail call void @llvm.memcpy.p0.p0.i64(ptr [[DST]], ptr [[SRC]], i64 16, i1 false) ; CHECK-NEXT: ret i8 [[L]] ; tail call void @llvm.memcpy.p0.p0.i64(ptr %dst, ptr %src, i64 16, i1 false) store i8 99, ptr %src %l = load i8, ptr %dst tail call void @llvm.memcpy.p0.p0.i64(ptr %dst, ptr %src, i64 16, i1 false) ret i8 %l } ; The @use() call is a later non-removable store, but should not affect the ; removal of the store in the if block. define void @later_non_removable_store(i1 %c, ptr %p) { ; CHECK-LABEL: @later_non_removable_store( ; CHECK-NEXT: store i8 1, ptr [[P:%.*]], align 1 ; CHECK-NEXT: br i1 [[C:%.*]], label [[IF:%.*]], label [[EXIT:%.*]] ; CHECK: if: ; CHECK-NEXT: br label [[EXIT]] ; CHECK: exit: ; CHECK-NEXT: call void @use(ptr [[P]]) #[[ATTR6:[0-9]+]] ; CHECK-NEXT: ret void ; store i8 1, ptr %p br i1 %c, label %if, label %exit if: store i8 1, ptr %p br label %exit exit: call void @use(ptr %p) argmemonly ret void }