; NOTE: Assertions have been autogenerated by utils/update_test_checks.py ; RUN: opt -passes='loop-mssa(unswitch),verify' -S < %s | FileCheck %s declare void @clobber() define i32 @partial_unswitch_true_successor(i32* %ptr, i32 %N) { ; CHECK-LABEL: @partial_unswitch_true_successor( ; CHECK-NEXT: entry: ; CHECK-NEXT: br label [[LOOP_HEADER:%.*]] ; CHECK: loop.header: ; CHECK-NEXT: [[IV:%.*]] = phi i32 [ 0, [[ENTRY:%.*]] ], [ [[IV_NEXT:%.*]], [[LOOP_LATCH:%.*]] ] ; CHECK-NEXT: [[LV:%.*]] = load i32, i32* [[PTR:%.*]], align 4 ; CHECK-NEXT: [[SC:%.*]] = icmp eq i32 [[LV]], 100 ; CHECK-NEXT: br i1 [[SC]], label [[NOCLOBBER:%.*]], label [[CLOBBER:%.*]] ; CHECK: noclobber: ; CHECK-NEXT: br label [[LOOP_LATCH]] ; CHECK: clobber: ; CHECK-NEXT: call void @clobber() ; CHECK-NEXT: br label [[LOOP_LATCH]] ; CHECK: loop.latch: ; CHECK-NEXT: [[C:%.*]] = icmp ult i32 [[IV]], [[N:%.*]] ; CHECK-NEXT: [[IV_NEXT]] = add i32 [[IV]], 1 ; CHECK-NEXT: br i1 [[C]], label [[LOOP_HEADER]], label [[EXIT:%.*]] ; CHECK: exit: ; CHECK-NEXT: ret i32 10 ; entry: br label %loop.header loop.header: %iv = phi i32 [ 0, %entry ], [ %iv.next, %loop.latch ] %lv = load i32, i32* %ptr %sc = icmp eq i32 %lv, 100 br i1 %sc, label %noclobber, label %clobber noclobber: br label %loop.latch clobber: call void @clobber() br label %loop.latch loop.latch: %c = icmp ult i32 %iv, %N %iv.next = add i32 %iv, 1 br i1 %c, label %loop.header, label %exit exit: ret i32 10 } define i32 @partial_unswitch_false_successor(i32* %ptr, i32 %N) { ; CHECK-LABEL: @partial_unswitch_false_successor( ; CHECK-NEXT: entry: ; CHECK-NEXT: br label [[LOOP_HEADER:%.*]] ; CHECK: loop.header: ; CHECK-NEXT: [[IV:%.*]] = phi i32 [ 0, [[ENTRY:%.*]] ], [ [[IV_NEXT:%.*]], [[LOOP_LATCH:%.*]] ] ; CHECK-NEXT: [[LV:%.*]] = load i32, i32* [[PTR:%.*]], align 4 ; CHECK-NEXT: [[SC:%.*]] = icmp eq i32 [[LV]], 100 ; CHECK-NEXT: br i1 [[SC]], label [[CLOBBER:%.*]], label [[NOCLOBBER:%.*]] ; CHECK: clobber: ; CHECK-NEXT: call void @clobber() ; CHECK-NEXT: br label [[LOOP_LATCH]] ; CHECK: noclobber: ; CHECK-NEXT: br label [[LOOP_LATCH]] ; CHECK: loop.latch: ; CHECK-NEXT: [[C:%.*]] = icmp ult i32 [[IV]], [[N:%.*]] ; CHECK-NEXT: [[IV_NEXT]] = add i32 [[IV]], 1 ; CHECK-NEXT: br i1 [[C]], label [[LOOP_HEADER]], label [[EXIT:%.*]] ; CHECK: exit: ; CHECK-NEXT: ret i32 10 ; entry: br label %loop.header loop.header: %iv = phi i32 [ 0, %entry ], [ %iv.next, %loop.latch ] %lv = load i32, i32* %ptr %sc = icmp eq i32 %lv, 100 br i1 %sc, label %clobber, label %noclobber clobber: call void @clobber() br label %loop.latch noclobber: br label %loop.latch loop.latch: %c = icmp ult i32 %iv, %N %iv.next = add i32 %iv, 1 br i1 %c, label %loop.header, label %exit exit: ret i32 10 } define i32 @partial_unswtich_gep_load_icmp(i32** %ptr, i32 %N) { ; CHECK-LABEL: @partial_unswtich_gep_load_icmp( ; CHECK-NEXT: entry: ; CHECK-NEXT: br label [[LOOP_HEADER:%.*]] ; CHECK: loop.header: ; CHECK-NEXT: [[IV:%.*]] = phi i32 [ 0, [[ENTRY:%.*]] ], [ [[IV_NEXT:%.*]], [[LOOP_LATCH:%.*]] ] ; CHECK-NEXT: [[GEP:%.*]] = getelementptr i32*, i32** [[PTR:%.*]], i32 1 ; CHECK-NEXT: [[LV_1:%.*]] = load i32*, i32** [[GEP]], align 8 ; CHECK-NEXT: [[LV:%.*]] = load i32, i32* [[LV_1]], align 4 ; CHECK-NEXT: [[SC:%.*]] = icmp eq i32 [[LV]], 100 ; CHECK-NEXT: br i1 [[SC]], label [[NOCLOBBER:%.*]], label [[CLOBBER:%.*]] ; CHECK: noclobber: ; CHECK-NEXT: br label [[LOOP_LATCH]] ; CHECK: clobber: ; CHECK-NEXT: call void @clobber() ; CHECK-NEXT: br label [[LOOP_LATCH]] ; CHECK: loop.latch: ; CHECK-NEXT: [[C:%.*]] = icmp ult i32 [[IV]], [[N:%.*]] ; CHECK-NEXT: [[IV_NEXT]] = add i32 [[IV]], 1 ; CHECK-NEXT: br i1 [[C]], label [[LOOP_HEADER]], label [[EXIT:%.*]] ; CHECK: exit: ; CHECK-NEXT: ret i32 10 ; entry: br label %loop.header loop.header: %iv = phi i32 [ 0, %entry ], [ %iv.next, %loop.latch ] %gep = getelementptr i32*, i32** %ptr, i32 1 %lv.1 = load i32*, i32** %gep %lv = load i32, i32* %lv.1 %sc = icmp eq i32 %lv, 100 br i1 %sc, label %noclobber, label %clobber noclobber: br label %loop.latch clobber: call void @clobber() br label %loop.latch loop.latch: %c = icmp ult i32 %iv, %N %iv.next = add i32 %iv, 1 br i1 %c, label %loop.header, label %exit exit: ret i32 10 } define i32 @partial_unswitch_reduction_phi(i32* %ptr, i32 %N) { ; CHECK-LABEL: @partial_unswitch_reduction_phi( ; CHECK-NEXT: entry: ; CHECK-NEXT: br label [[LOOP_HEADER:%.*]] ; CHECK: loop.header: ; CHECK-NEXT: [[IV:%.*]] = phi i32 [ 0, [[ENTRY:%.*]] ], [ [[IV_NEXT:%.*]], [[LOOP_LATCH:%.*]] ] ; CHECK-NEXT: [[RED:%.*]] = phi i32 [ 20, [[ENTRY]] ], [ [[RED_NEXT:%.*]], [[LOOP_LATCH]] ] ; CHECK-NEXT: [[LV:%.*]] = load i32, i32* [[PTR:%.*]], align 4 ; CHECK-NEXT: [[SC:%.*]] = icmp eq i32 [[LV]], 100 ; CHECK-NEXT: br i1 [[SC]], label [[CLOBBER:%.*]], label [[NOCLOBBER:%.*]] ; CHECK: clobber: ; CHECK-NEXT: call void @clobber() ; CHECK-NEXT: [[ADD_5:%.*]] = add i32 [[RED]], 5 ; CHECK-NEXT: br label [[LOOP_LATCH]] ; CHECK: noclobber: ; CHECK-NEXT: [[ADD_10:%.*]] = add i32 [[RED]], 10 ; CHECK-NEXT: br label [[LOOP_LATCH]] ; CHECK: loop.latch: ; CHECK-NEXT: [[RED_NEXT]] = phi i32 [ [[ADD_5]], [[CLOBBER]] ], [ [[ADD_10]], [[NOCLOBBER]] ] ; CHECK-NEXT: [[C:%.*]] = icmp ult i32 [[IV]], [[N:%.*]] ; CHECK-NEXT: [[IV_NEXT]] = add i32 [[IV]], 1 ; CHECK-NEXT: br i1 [[C]], label [[LOOP_HEADER]], label [[EXIT:%.*]] ; CHECK: exit: ; CHECK-NEXT: [[RED_NEXT_LCSSA:%.*]] = phi i32 [ [[RED_NEXT]], [[LOOP_LATCH]] ] ; CHECK-NEXT: ret i32 [[RED_NEXT_LCSSA]] ; entry: br label %loop.header loop.header: %iv = phi i32 [ 0, %entry ], [ %iv.next, %loop.latch ] %red = phi i32 [ 20, %entry ], [ %red.next, %loop.latch ] %lv = load i32, i32* %ptr %sc = icmp eq i32 %lv, 100 br i1 %sc, label %clobber, label %noclobber clobber: call void @clobber() %add.5 = add i32 %red, 5 br label %loop.latch noclobber: %add.10 = add i32 %red, 10 br label %loop.latch loop.latch: %red.next = phi i32 [ %add.5, %clobber ], [ %add.10, %noclobber ] %c = icmp ult i32 %iv, %N %iv.next = add i32 %iv, 1 br i1 %c, label %loop.header, label %exit exit: %red.next.lcssa = phi i32 [ %red.next, %loop.latch ] ret i32 %red.next.lcssa } ; Partial unswitching is possible, because the store in %noclobber does not ; alias the load of the condition. define i32 @partial_unswitch_true_successor_noclobber(i32* noalias %ptr.1, i32* noalias %ptr.2, i32 %N) { ; CHECK-LABEL: @partial_unswitch_true_successor_noclobber( ; CHECK-NEXT: entry: ; CHECK-NEXT: br label [[LOOP_HEADER:%.*]] ; CHECK: loop.header: ; CHECK-NEXT: [[IV:%.*]] = phi i32 [ 0, [[ENTRY:%.*]] ], [ [[IV_NEXT:%.*]], [[LOOP_LATCH:%.*]] ] ; CHECK-NEXT: [[LV:%.*]] = load i32, i32* [[PTR_1:%.*]], align 4 ; CHECK-NEXT: [[SC:%.*]] = icmp eq i32 [[LV]], 100 ; CHECK-NEXT: br i1 [[SC]], label [[NOCLOBBER:%.*]], label [[CLOBBER:%.*]] ; CHECK: noclobber: ; CHECK-NEXT: [[GEP_1:%.*]] = getelementptr i32, i32* [[PTR_2:%.*]], i32 [[IV]] ; CHECK-NEXT: store i32 [[LV]], i32* [[GEP_1]], align 4 ; CHECK-NEXT: br label [[LOOP_LATCH]] ; CHECK: clobber: ; CHECK-NEXT: call void @clobber() ; CHECK-NEXT: br label [[LOOP_LATCH]] ; CHECK: loop.latch: ; CHECK-NEXT: [[C:%.*]] = icmp ult i32 [[IV]], [[N:%.*]] ; CHECK-NEXT: [[IV_NEXT]] = add i32 [[IV]], 1 ; CHECK-NEXT: br i1 [[C]], label [[LOOP_HEADER]], label [[EXIT:%.*]] ; CHECK: exit: ; CHECK-NEXT: ret i32 10 ; entry: br label %loop.header loop.header: %iv = phi i32 [ 0, %entry ], [ %iv.next, %loop.latch ] %lv = load i32, i32* %ptr.1 %sc = icmp eq i32 %lv, 100 br i1 %sc, label %noclobber, label %clobber noclobber: %gep.1 = getelementptr i32, i32* %ptr.2, i32 %iv store i32 %lv, i32* %gep.1 br label %loop.latch clobber: call void @clobber() br label %loop.latch loop.latch: %c = icmp ult i32 %iv, %N %iv.next = add i32 %iv, 1 br i1 %c, label %loop.header, label %exit exit: ret i32 10 } define void @no_partial_unswitch_phi_cond(i1 %lc, i32 %N) { ; CHECK-LABEL: @no_partial_unswitch_phi_cond( ; CHECK-NEXT: entry: ; CHECK-NEXT: br label [[LOOP_HEADER:%.*]] ; CHECK: loop.header: ; CHECK-NEXT: [[IV:%.*]] = phi i32 [ 0, [[ENTRY:%.*]] ], [ [[IV_NEXT:%.*]], [[LOOP_LATCH:%.*]] ] ; CHECK-NEXT: [[SC:%.*]] = phi i1 [ [[LC:%.*]], [[ENTRY]] ], [ true, [[LOOP_LATCH]] ] ; CHECK-NEXT: br i1 [[SC]], label [[CLOBBER:%.*]], label [[NOCLOBBER:%.*]] ; CHECK: clobber: ; CHECK-NEXT: call void @clobber() ; CHECK-NEXT: br label [[LOOP_LATCH]] ; CHECK: noclobber: ; CHECK-NEXT: br label [[LOOP_LATCH]] ; CHECK: loop.latch: ; CHECK-NEXT: [[C:%.*]] = icmp ult i32 [[IV]], [[N:%.*]] ; CHECK-NEXT: [[IV_NEXT]] = add i32 [[IV]], 1 ; CHECK-NEXT: br i1 [[C]], label [[LOOP_HEADER]], label [[EXIT:%.*]] ; CHECK: exit: ; CHECK-NEXT: ret void ; entry: br label %loop.header loop.header: %iv = phi i32 [ 0, %entry ], [ %iv.next, %loop.latch ] %sc = phi i1 [ %lc, %entry ], [ true, %loop.latch ] br i1 %sc, label %clobber, label %noclobber clobber: call void @clobber() br label %loop.latch noclobber: br label %loop.latch loop.latch: %c = icmp ult i32 %iv, %N %iv.next = add i32 %iv, 1 br i1 %c, label %loop.header, label %exit exit: ret void } define void @no_partial_unswitch_clobber_latch(i32* %ptr, i32 %N) { ; CHECK-LABEL: @no_partial_unswitch_clobber_latch( ; CHECK-NEXT: entry: ; CHECK-NEXT: br label [[LOOP_HEADER:%.*]] ; CHECK: loop.header: ; CHECK-NEXT: [[IV:%.*]] = phi i32 [ 0, [[ENTRY:%.*]] ], [ [[IV_NEXT:%.*]], [[LOOP_LATCH:%.*]] ] ; CHECK-NEXT: [[LV:%.*]] = load i32, i32* [[PTR:%.*]], align 4 ; CHECK-NEXT: [[SC:%.*]] = icmp eq i32 [[LV]], 100 ; CHECK-NEXT: br i1 [[SC]], label [[NOCLOBBER:%.*]], label [[CLOBBER:%.*]] ; CHECK: noclobber: ; CHECK-NEXT: br label [[LOOP_LATCH]] ; CHECK: clobber: ; CHECK-NEXT: call void @clobber() ; CHECK-NEXT: br label [[LOOP_LATCH]] ; CHECK: loop.latch: ; CHECK-NEXT: call void @clobber() ; CHECK-NEXT: [[C:%.*]] = icmp ult i32 [[IV]], [[N:%.*]] ; CHECK-NEXT: [[IV_NEXT]] = add i32 [[IV]], 1 ; CHECK-NEXT: br i1 [[C]], label [[LOOP_HEADER]], label [[EXIT:%.*]] ; CHECK: exit: ; CHECK-NEXT: ret void ; entry: br label %loop.header loop.header: %iv = phi i32 [ 0, %entry ], [ %iv.next, %loop.latch ] %lv = load i32, i32* %ptr %sc = icmp eq i32 %lv, 100 br i1 %sc, label %noclobber, label %clobber noclobber: br label %loop.latch clobber: call void @clobber() br label %loop.latch loop.latch: call void @clobber() %c = icmp ult i32 %iv, %N %iv.next = add i32 %iv, 1 br i1 %c, label %loop.header, label %exit exit: ret void } define void @no_partial_unswitch_clobber_header(i32* %ptr, i32 %N) { ; CHECK-LABEL: @no_partial_unswitch_clobber_header( ; CHECK-NEXT: entry: ; CHECK-NEXT: br label [[LOOP_HEADER:%.*]] ; CHECK: loop.header: ; CHECK-NEXT: [[IV:%.*]] = phi i32 [ 0, [[ENTRY:%.*]] ], [ [[IV_NEXT:%.*]], [[LOOP_LATCH:%.*]] ] ; CHECK-NEXT: call void @clobber() ; CHECK-NEXT: [[LV:%.*]] = load i32, i32* [[PTR:%.*]], align 4 ; CHECK-NEXT: [[SC:%.*]] = icmp eq i32 [[LV]], 100 ; CHECK-NEXT: br i1 [[SC]], label [[NOCLOBBER:%.*]], label [[CLOBBER:%.*]] ; CHECK: noclobber: ; CHECK-NEXT: br label [[LOOP_LATCH]] ; CHECK: clobber: ; CHECK-NEXT: call void @clobber() ; CHECK-NEXT: br label [[LOOP_LATCH]] ; CHECK: loop.latch: ; CHECK-NEXT: [[C:%.*]] = icmp ult i32 [[IV]], [[N:%.*]] ; CHECK-NEXT: [[IV_NEXT]] = add i32 [[IV]], 1 ; CHECK-NEXT: br i1 [[C]], label [[LOOP_HEADER]], label [[EXIT:%.*]] ; CHECK: exit: ; CHECK-NEXT: ret void ; entry: br label %loop.header loop.header: %iv = phi i32 [ 0, %entry ], [ %iv.next, %loop.latch ] call void @clobber() %lv = load i32, i32* %ptr %sc = icmp eq i32 %lv, 100 br i1 %sc, label %noclobber, label %clobber noclobber: br label %loop.latch clobber: call void @clobber() br label %loop.latch loop.latch: %c = icmp ult i32 %iv, %N %iv.next = add i32 %iv, 1 br i1 %c, label %loop.header, label %exit exit: ret void } define void @no_partial_unswitch_clobber_both(i32* %ptr, i32 %N) { ; CHECK-LABEL: @no_partial_unswitch_clobber_both( ; CHECK-NEXT: entry: ; CHECK-NEXT: br label [[LOOP_HEADER:%.*]] ; CHECK: loop.header: ; CHECK-NEXT: [[IV:%.*]] = phi i32 [ 0, [[ENTRY:%.*]] ], [ [[IV_NEXT:%.*]], [[LOOP_LATCH:%.*]] ] ; CHECK-NEXT: [[LV:%.*]] = load i32, i32* [[PTR:%.*]], align 4 ; CHECK-NEXT: [[SC:%.*]] = icmp eq i32 [[LV]], 100 ; CHECK-NEXT: br i1 [[SC]], label [[NOCLOBBER:%.*]], label [[CLOBBER:%.*]] ; CHECK: noclobber: ; CHECK-NEXT: call void @clobber() ; CHECK-NEXT: br label [[LOOP_LATCH]] ; CHECK: clobber: ; CHECK-NEXT: call void @clobber() ; CHECK-NEXT: br label [[LOOP_LATCH]] ; CHECK: loop.latch: ; CHECK-NEXT: [[C:%.*]] = icmp ult i32 [[IV]], [[N:%.*]] ; CHECK-NEXT: [[IV_NEXT]] = add i32 [[IV]], 1 ; CHECK-NEXT: br i1 [[C]], label [[LOOP_HEADER]], label [[EXIT:%.*]] ; CHECK: exit: ; CHECK-NEXT: ret void ; entry: br label %loop.header loop.header: %iv = phi i32 [ 0, %entry ], [ %iv.next, %loop.latch ] %lv = load i32, i32* %ptr %sc = icmp eq i32 %lv, 100 br i1 %sc, label %noclobber, label %clobber noclobber: call void @clobber() br label %loop.latch clobber: call void @clobber() br label %loop.latch loop.latch: %c = icmp ult i32 %iv, %N %iv.next = add i32 %iv, 1 br i1 %c, label %loop.header, label %exit exit: ret void } define i32 @no_partial_unswitch_true_successor_storeclobber(i32* %ptr.1, i32* %ptr.2, i32 %N) { ; CHECK-LABEL: @no_partial_unswitch_true_successor_storeclobber( ; CHECK-NEXT: entry: ; CHECK-NEXT: br label [[LOOP_HEADER:%.*]] ; CHECK: loop.header: ; CHECK-NEXT: [[IV:%.*]] = phi i32 [ 0, [[ENTRY:%.*]] ], [ [[IV_NEXT:%.*]], [[LOOP_LATCH:%.*]] ] ; CHECK-NEXT: [[LV:%.*]] = load i32, i32* [[PTR_1:%.*]], align 4 ; CHECK-NEXT: [[SC:%.*]] = icmp eq i32 [[LV]], 100 ; CHECK-NEXT: br i1 [[SC]], label [[NOCLOBBER:%.*]], label [[CLOBBER:%.*]] ; CHECK: noclobber: ; CHECK-NEXT: [[GEP_1:%.*]] = getelementptr i32, i32* [[PTR_2:%.*]], i32 [[IV]] ; CHECK-NEXT: store i32 [[LV]], i32* [[GEP_1]], align 4 ; CHECK-NEXT: br label [[LOOP_LATCH]] ; CHECK: clobber: ; CHECK-NEXT: call void @clobber() ; CHECK-NEXT: br label [[LOOP_LATCH]] ; CHECK: loop.latch: ; CHECK-NEXT: [[C:%.*]] = icmp ult i32 [[IV]], [[N:%.*]] ; CHECK-NEXT: [[IV_NEXT]] = add i32 [[IV]], 1 ; CHECK-NEXT: br i1 [[C]], label [[LOOP_HEADER]], label [[EXIT:%.*]] ; CHECK: exit: ; CHECK-NEXT: ret i32 10 ; entry: br label %loop.header loop.header: %iv = phi i32 [ 0, %entry ], [ %iv.next, %loop.latch ] %lv = load i32, i32* %ptr.1 %sc = icmp eq i32 %lv, 100 br i1 %sc, label %noclobber, label %clobber noclobber: %gep.1 = getelementptr i32, i32* %ptr.2, i32 %iv store i32 %lv, i32* %gep.1 br label %loop.latch clobber: call void @clobber() br label %loop.latch loop.latch: %c = icmp ult i32 %iv, %N %iv.next = add i32 %iv, 1 br i1 %c, label %loop.header, label %exit exit: ret i32 10 } ; Make sure the duplicated instructions are moved to a preheader that always ; executes when the loop body also executes. Do not check the unswitched code, ; because it is already checked in the @partial_unswitch_true_successor test ; case. define i32 @partial_unswitch_true_successor_preheader_insertion(i32* %ptr, i32 %N) { ; CHECK-LABEL: @partial_unswitch_true_successor_preheader_insertion( ; CHECK-NEXT: entry: ; CHECK-NEXT: [[EC:%.*]] = icmp ne i32* [[PTR:%.*]], null ; CHECK-NEXT: br i1 [[EC]], label [[LOOP_PH:%.*]], label [[EXIT:%.*]] ; CHECK: loop.ph: ; CHECK-NEXT: br label [[LOOP_HEADER:%.*]] ; CHECK: loop.header: ; CHECK-NEXT: [[IV:%.*]] = phi i32 [ 0, [[LOOP_PH]] ], [ [[IV_NEXT:%.*]], [[LOOP_LATCH:%.*]] ] ; CHECK-NEXT: [[LV:%.*]] = load i32, i32* [[PTR]], align 4 ; CHECK-NEXT: [[SC:%.*]] = icmp eq i32 [[LV]], 100 ; CHECK-NEXT: br i1 [[SC]], label [[NOCLOBBER:%.*]], label [[CLOBBER:%.*]] ; CHECK: noclobber: ; CHECK-NEXT: br label [[LOOP_LATCH]] ; CHECK: clobber: ; CHECK-NEXT: call void @clobber() ; CHECK-NEXT: br label [[LOOP_LATCH]] ; CHECK: loop.latch: ; CHECK-NEXT: [[C:%.*]] = icmp ult i32 [[IV]], [[N:%.*]] ; CHECK-NEXT: [[IV_NEXT]] = add i32 [[IV]], 1 ; CHECK-NEXT: br i1 [[C]], label [[LOOP_HEADER]], label [[EXIT_LOOPEXIT:%.*]] ; CHECK: exit.loopexit: ; CHECK-NEXT: br label [[EXIT]] ; CHECK: exit: ; CHECK-NEXT: ret i32 10 ; entry: %ec = icmp ne i32* %ptr, null br i1 %ec, label %loop.ph, label %exit loop.ph: br label %loop.header loop.header: %iv = phi i32 [ 0, %loop.ph ], [ %iv.next, %loop.latch ] %lv = load i32, i32* %ptr %sc = icmp eq i32 %lv, 100 br i1 %sc, label %noclobber, label %clobber noclobber: br label %loop.latch clobber: call void @clobber() br label %loop.latch loop.latch: %c = icmp ult i32 %iv, %N %iv.next = add i32 %iv, 1 br i1 %c, label %loop.header, label %exit exit: ret i32 10 } ; Make sure the duplicated instructions are hoisted just before the branch of ; the preheader. Do not check the unswitched code, because it is already checked ; in the @partial_unswitch_true_successor test case define i32 @partial_unswitch_true_successor_insert_point(i32* %ptr, i32 %N) { ; CHECK-LABEL: @partial_unswitch_true_successor_insert_point( ; CHECK-NEXT: entry: ; CHECK-NEXT: call void @clobber() ; CHECK-NEXT: br label [[LOOP_HEADER:%.*]] ; CHECK: loop.header: ; CHECK-NEXT: [[IV:%.*]] = phi i32 [ 0, [[ENTRY:%.*]] ], [ [[IV_NEXT:%.*]], [[LOOP_LATCH:%.*]] ] ; CHECK-NEXT: [[LV:%.*]] = load i32, i32* [[PTR:%.*]], align 4 ; CHECK-NEXT: [[SC:%.*]] = icmp eq i32 [[LV]], 100 ; CHECK-NEXT: br i1 [[SC]], label [[NOCLOBBER:%.*]], label [[CLOBBER:%.*]] ; CHECK: noclobber: ; CHECK-NEXT: br label [[LOOP_LATCH]] ; CHECK: clobber: ; CHECK-NEXT: call void @clobber() ; CHECK-NEXT: br label [[LOOP_LATCH]] ; CHECK: loop.latch: ; CHECK-NEXT: [[C:%.*]] = icmp ult i32 [[IV]], [[N:%.*]] ; CHECK-NEXT: [[IV_NEXT]] = add i32 [[IV]], 1 ; CHECK-NEXT: br i1 [[C]], label [[LOOP_HEADER]], label [[EXIT:%.*]] ; CHECK: exit: ; CHECK-NEXT: ret i32 10 ; entry: call void @clobber() br label %loop.header loop.header: %iv = phi i32 [ 0, %entry ], [ %iv.next, %loop.latch ] %lv = load i32, i32* %ptr %sc = icmp eq i32 %lv, 100 br i1 %sc, label %noclobber, label %clobber noclobber: br label %loop.latch clobber: call void @clobber() br label %loop.latch loop.latch: %c = icmp ult i32 %iv, %N %iv.next = add i32 %iv, 1 br i1 %c, label %loop.header, label %exit exit: ret i32 10 } ; Make sure invariant instructions in the loop are also hoisted to the preheader. ; Do not check the unswitched code, because it is already checked in the ; @partial_unswitch_true_successor test case define i32 @partial_unswitch_true_successor_hoist_invariant(i32* %ptr, i32 %N) { ; CHECK-LABEL: @partial_unswitch_true_successor_hoist_invariant( ; CHECK-NEXT: entry: ; CHECK-NEXT: br label [[LOOP_HEADER:%.*]] ; CHECK: loop.header: ; CHECK-NEXT: [[IV:%.*]] = phi i32 [ 0, [[ENTRY:%.*]] ], [ [[IV_NEXT:%.*]], [[LOOP_LATCH:%.*]] ] ; CHECK-NEXT: [[GEP:%.*]] = getelementptr i32, i32* [[PTR:%.*]], i64 1 ; CHECK-NEXT: [[LV:%.*]] = load i32, i32* [[GEP]], align 4 ; CHECK-NEXT: [[SC:%.*]] = icmp eq i32 [[LV]], 100 ; CHECK-NEXT: br i1 [[SC]], label [[NOCLOBBER:%.*]], label [[CLOBBER:%.*]] ; CHECK: noclobber: ; CHECK-NEXT: br label [[LOOP_LATCH]] ; CHECK: clobber: ; CHECK-NEXT: call void @clobber() ; CHECK-NEXT: br label [[LOOP_LATCH]] ; CHECK: loop.latch: ; CHECK-NEXT: [[C:%.*]] = icmp ult i32 [[IV]], [[N:%.*]] ; CHECK-NEXT: [[IV_NEXT]] = add i32 [[IV]], 1 ; CHECK-NEXT: br i1 [[C]], label [[LOOP_HEADER]], label [[EXIT:%.*]] ; CHECK: exit: ; CHECK-NEXT: ret i32 10 ; entry: br label %loop.header loop.header: %iv = phi i32 [ 0, %entry ], [ %iv.next, %loop.latch ] %gep = getelementptr i32, i32* %ptr, i64 1 %lv = load i32, i32* %gep %sc = icmp eq i32 %lv, 100 br i1 %sc, label %noclobber, label %clobber noclobber: br label %loop.latch clobber: call void @clobber() br label %loop.latch loop.latch: %c = icmp ult i32 %iv, %N %iv.next = add i32 %iv, 1 br i1 %c, label %loop.header, label %exit exit: ret i32 10 } ; Do not unswitch if the condition depends on an atomic load. Duplicating such ; loads is not safe. define i32 @no_partial_unswitch_atomic_load_unordered(i32* %ptr, i32 %N) { ; CHECK-LABEL: @no_partial_unswitch_atomic_load_unordered( ; CHECK-NEXT: entry: ; CHECK-NEXT: br label [[LOOP_HEADER:%.*]] ; CHECK: loop.header: ; CHECK-NEXT: [[IV:%.*]] = phi i32 [ 0, [[ENTRY:%.*]] ], [ [[IV_NEXT:%.*]], [[LOOP_LATCH:%.*]] ] ; CHECK-NEXT: [[LV:%.*]] = load atomic i32, i32* [[PTR:%.*]] unordered, align 4 ; CHECK-NEXT: [[SC:%.*]] = icmp eq i32 [[LV]], 100 ; CHECK-NEXT: br i1 [[SC]], label [[NOCLOBBER:%.*]], label [[CLOBBER:%.*]] ; CHECK: noclobber: ; CHECK-NEXT: br label [[LOOP_LATCH]] ; CHECK: clobber: ; CHECK-NEXT: call void @clobber() ; CHECK-NEXT: br label [[LOOP_LATCH]] ; CHECK: loop.latch: ; CHECK-NEXT: [[C:%.*]] = icmp ult i32 [[IV]], [[N:%.*]] ; CHECK-NEXT: [[IV_NEXT]] = add i32 [[IV]], 1 ; CHECK-NEXT: br i1 [[C]], label [[LOOP_HEADER]], label [[EXIT:%.*]] ; CHECK: exit: ; CHECK-NEXT: ret i32 10 ; entry: br label %loop.header loop.header: %iv = phi i32 [ 0, %entry ], [ %iv.next, %loop.latch ] %lv = load atomic i32, i32* %ptr unordered, align 4 %sc = icmp eq i32 %lv, 100 br i1 %sc, label %noclobber, label %clobber noclobber: br label %loop.latch clobber: call void @clobber() br label %loop.latch loop.latch: %c = icmp ult i32 %iv, %N %iv.next = add i32 %iv, 1 br i1 %c, label %loop.header, label %exit exit: ret i32 10 } ; Do not unswitch if the condition depends on an atomic load. Duplicating such ; loads is not safe. define i32 @no_partial_unswitch_atomic_load_monotonic(i32* %ptr, i32 %N) { ; CHECK-LABEL: @no_partial_unswitch_atomic_load_monotonic( ; CHECK-NEXT: entry: ; CHECK-NEXT: br label [[LOOP_HEADER:%.*]] ; CHECK: loop.header: ; CHECK-NEXT: [[IV:%.*]] = phi i32 [ 0, [[ENTRY:%.*]] ], [ [[IV_NEXT:%.*]], [[LOOP_LATCH:%.*]] ] ; CHECK-NEXT: [[LV:%.*]] = load atomic i32, i32* [[PTR:%.*]] monotonic, align 4 ; CHECK-NEXT: [[SC:%.*]] = icmp eq i32 [[LV]], 100 ; CHECK-NEXT: br i1 [[SC]], label [[NOCLOBBER:%.*]], label [[CLOBBER:%.*]] ; CHECK: noclobber: ; CHECK-NEXT: br label [[LOOP_LATCH]] ; CHECK: clobber: ; CHECK-NEXT: call void @clobber() ; CHECK-NEXT: br label [[LOOP_LATCH]] ; CHECK: loop.latch: ; CHECK-NEXT: [[C:%.*]] = icmp ult i32 [[IV]], [[N:%.*]] ; CHECK-NEXT: [[IV_NEXT]] = add i32 [[IV]], 1 ; CHECK-NEXT: br i1 [[C]], label [[LOOP_HEADER]], label [[EXIT:%.*]] ; CHECK: exit: ; CHECK-NEXT: ret i32 10 ; entry: br label %loop.header loop.header: %iv = phi i32 [ 0, %entry ], [ %iv.next, %loop.latch ] %lv = load atomic i32, i32* %ptr monotonic, align 4 %sc = icmp eq i32 %lv, 100 br i1 %sc, label %noclobber, label %clobber noclobber: br label %loop.latch clobber: call void @clobber() br label %loop.latch loop.latch: %c = icmp ult i32 %iv, %N %iv.next = add i32 %iv, 1 br i1 %c, label %loop.header, label %exit exit: ret i32 10 } declare i32 @get_value() ; Do not unswitch if the condition depends on a call, that may clobber memory. ; Duplicating such a call is not safe. define i32 @no_partial_unswitch_cond_call(i32* %ptr, i32 %N) { ; CHECK-LABEL: @no_partial_unswitch_cond_call( ; CHECK-NEXT: entry: ; CHECK-NEXT: br label [[LOOP_HEADER:%.*]] ; CHECK: loop.header: ; CHECK-NEXT: [[IV:%.*]] = phi i32 [ 0, [[ENTRY:%.*]] ], [ [[IV_NEXT:%.*]], [[LOOP_LATCH:%.*]] ] ; CHECK-NEXT: [[LV:%.*]] = call i32 @get_value() ; CHECK-NEXT: [[SC:%.*]] = icmp eq i32 [[LV]], 100 ; CHECK-NEXT: br i1 [[SC]], label [[NOCLOBBER:%.*]], label [[CLOBBER:%.*]] ; CHECK: noclobber: ; CHECK-NEXT: br label [[LOOP_LATCH]] ; CHECK: clobber: ; CHECK-NEXT: call void @clobber() ; CHECK-NEXT: br label [[LOOP_LATCH]] ; CHECK: loop.latch: ; CHECK-NEXT: [[C:%.*]] = icmp ult i32 [[IV]], [[N:%.*]] ; CHECK-NEXT: [[IV_NEXT]] = add i32 [[IV]], 1 ; CHECK-NEXT: br i1 [[C]], label [[LOOP_HEADER]], label [[EXIT:%.*]] ; CHECK: exit: ; CHECK-NEXT: ret i32 10 ; entry: br label %loop.header loop.header: %iv = phi i32 [ 0, %entry ], [ %iv.next, %loop.latch ] %lv = call i32 @get_value() %sc = icmp eq i32 %lv, 100 br i1 %sc, label %noclobber, label %clobber noclobber: br label %loop.latch clobber: call void @clobber() br label %loop.latch loop.latch: %c = icmp ult i32 %iv, %N %iv.next = add i32 %iv, 1 br i1 %c, label %loop.header, label %exit exit: ret i32 10 } define i32 @no_partial_unswitch_true_successor_exit(i32* %ptr, i32 %N) { ; CHECK-LABEL: @no_partial_unswitch_true_successor_exit( ; CHECK-NEXT: entry: ; CHECK-NEXT: br label [[LOOP_HEADER:%.*]] ; CHECK: loop.header: ; CHECK-NEXT: [[IV:%.*]] = phi i32 [ 0, [[ENTRY:%.*]] ], [ [[IV_NEXT:%.*]], [[LOOP_LATCH:%.*]] ] ; CHECK-NEXT: [[LV:%.*]] = load i32, i32* [[PTR:%.*]], align 4 ; CHECK-NEXT: [[SC:%.*]] = icmp eq i32 [[LV]], 100 ; CHECK-NEXT: br i1 [[SC]], label [[EXIT:%.*]], label [[CLOBBER:%.*]] ; CHECK: clobber: ; CHECK-NEXT: call void @clobber() ; CHECK-NEXT: br label [[LOOP_LATCH]] ; CHECK: loop.latch: ; CHECK-NEXT: [[C:%.*]] = icmp ult i32 [[IV]], [[N:%.*]] ; CHECK-NEXT: [[IV_NEXT]] = add i32 [[IV]], 1 ; CHECK-NEXT: br i1 [[C]], label [[LOOP_HEADER]], label [[EXIT]] ; CHECK: exit: ; CHECK-NEXT: ret i32 10 ; entry: br label %loop.header loop.header: %iv = phi i32 [ 0, %entry ], [ %iv.next, %loop.latch ] %lv = load i32, i32* %ptr %sc = icmp eq i32 %lv, 100 br i1 %sc, label %exit, label %clobber clobber: call void @clobber() br label %loop.latch loop.latch: %c = icmp ult i32 %iv, %N %iv.next = add i32 %iv, 1 br i1 %c, label %loop.header, label %exit exit: ret i32 10 } define i32 @no_partial_unswitch_true_same_successor(i32* %ptr, i32 %N) { ; CHECK-LABEL: @no_partial_unswitch_true_same_successor( ; CHECK-NEXT: entry: ; CHECK-NEXT: br label [[LOOP_HEADER:%.*]] ; CHECK: loop.header: ; CHECK-NEXT: [[IV:%.*]] = phi i32 [ 0, [[ENTRY:%.*]] ], [ [[IV_NEXT:%.*]], [[LOOP_LATCH:%.*]] ] ; CHECK-NEXT: [[LV:%.*]] = load i32, i32* [[PTR:%.*]], align 4 ; CHECK-NEXT: [[SC:%.*]] = icmp eq i32 [[LV]], 100 ; CHECK-NEXT: br i1 [[SC]], label [[NOCLOBBER:%.*]], label [[NOCLOBBER]] ; CHECK: noclobber: ; CHECK-NEXT: br label [[LOOP_LATCH]] ; CHECK: loop.latch: ; CHECK-NEXT: [[C:%.*]] = icmp ult i32 [[IV]], [[N:%.*]] ; CHECK-NEXT: [[IV_NEXT]] = add i32 [[IV]], 1 ; CHECK-NEXT: br i1 [[C]], label [[LOOP_HEADER]], label [[EXIT:%.*]] ; CHECK: exit: ; CHECK-NEXT: ret i32 10 ; entry: br label %loop.header loop.header: %iv = phi i32 [ 0, %entry ], [ %iv.next, %loop.latch ] %lv = load i32, i32* %ptr %sc = icmp eq i32 %lv, 100 br i1 %sc, label %noclobber, label %noclobber noclobber: br label %loop.latch loop.latch: %c = icmp ult i32 %iv, %N %iv.next = add i32 %iv, 1 br i1 %c, label %loop.header, label %exit exit: ret i32 10 } define i32 @partial_unswitch_true_to_latch(i32* %ptr, i32 %N) { ; CHECK-LABEL: @partial_unswitch_true_to_latch( ; CHECK-NEXT: entry: ; CHECK-NEXT: br label [[LOOP_HEADER:%.*]] ; CHECK: loop.header: ; CHECK-NEXT: [[IV:%.*]] = phi i32 [ 0, [[ENTRY:%.*]] ], [ [[IV_NEXT:%.*]], [[LOOP_LATCH:%.*]] ] ; CHECK-NEXT: [[LV:%.*]] = load i32, i32* [[PTR:%.*]], align 4 ; CHECK-NEXT: [[SC:%.*]] = icmp eq i32 [[LV]], 100 ; CHECK-NEXT: br i1 [[SC]], label [[LOOP_LATCH]], label [[CLOBBER:%.*]] ; CHECK: clobber: ; CHECK-NEXT: call void @clobber() ; CHECK-NEXT: br label [[LOOP_LATCH]] ; CHECK: loop.latch: ; CHECK-NEXT: [[C:%.*]] = icmp ult i32 [[IV]], [[N:%.*]] ; CHECK-NEXT: [[IV_NEXT]] = add i32 [[IV]], 1 ; CHECK-NEXT: br i1 [[C]], label [[LOOP_HEADER]], label [[EXIT:%.*]] ; CHECK: exit: ; CHECK-NEXT: ret i32 10 ; entry: br label %loop.header loop.header: %iv = phi i32 [ 0, %entry ], [ %iv.next, %loop.latch ] %lv = load i32, i32* %ptr %sc = icmp eq i32 %lv, 100 br i1 %sc, label %loop.latch, label %clobber clobber: call void @clobber() br label %loop.latch loop.latch: %c = icmp ult i32 %iv, %N %iv.next = add i32 %iv, 1 br i1 %c, label %loop.header, label %exit exit: ret i32 10 }