; NOTE: Assertions have been autogenerated by utils/update_test_checks.py ; RUN: opt < %s -passes='simplifycfg' -simplifycfg-require-and-preserve-domtree=1 -S | FileCheck %s define i1 @common_instr_with_unreachable(i64 %a, i64 %b, i64 %c) { ; CHECK-LABEL: @common_instr_with_unreachable( ; CHECK-NEXT: start: ; CHECK-NEXT: [[TMP0:%.*]] = icmp eq i64 [[B:%.*]], [[C:%.*]] ; CHECK-NEXT: ret i1 [[TMP0]] ; start: switch i64 %a, label %unreachable [ i64 0, label %bb0 i64 1, label %bb1 i64 2, label %bb2 ] unreachable: unreachable bb0: ; preds = %start %0 = icmp eq i64 %b, %c br label %exit bb1: ; preds = %start %1 = icmp eq i64 %b, %c br label %exit bb2: ; preds = %start %2 = icmp eq i64 %b, %c br label %exit exit: ; preds = %bb2, %bb1, %bb0 %result = phi i1 [ %0, %bb0 ], [ %1, %bb1 ], [ %2, %bb2 ] ret i1 %result } define i1 @common_instr_with_unreachable_2(i64 %a, i64 %b, i64 %c) { ; CHECK-LABEL: @common_instr_with_unreachable_2( ; CHECK-NEXT: start: ; CHECK-NEXT: [[TMP0:%.*]] = icmp eq i64 [[B:%.*]], [[C:%.*]] ; CHECK-NEXT: ret i1 [[TMP0]] ; start: switch i64 %a, label %bb1 [ i64 0, label %bb0 i64 1, label %unreachable i64 2, label %bb2 ] unreachable: unreachable bb0: ; preds = %start %0 = icmp eq i64 %b, %c br label %exit bb1: ; preds = %start %1 = icmp eq i64 %b, %c br label %exit bb2: ; preds = %start %2 = icmp eq i64 %b, %c br label %exit exit: ; preds = %bb2, %bb1, %bb0 %result = phi i1 [ %0, %bb0 ], [ %1, %bb1 ], [ %2, %bb2 ] ret i1 %result } define i1 @not_only_unreachable(i64 %a, i64 %b, i64 %c) { ; CHECK-LABEL: @not_only_unreachable( ; CHECK-NEXT: start: ; CHECK-NEXT: switch i64 [[A:%.*]], label [[UNREACHABLE:%.*]] [ ; CHECK-NEXT: i64 0, label [[BB0:%.*]] ; CHECK-NEXT: i64 1, label [[BB1:%.*]] ; CHECK-NEXT: i64 2, label [[BB2:%.*]] ; CHECK-NEXT: ] ; CHECK: unreachable: ; CHECK-NEXT: call void @no_return() ; CHECK-NEXT: unreachable ; CHECK: bb0: ; CHECK-NEXT: [[TMP0:%.*]] = icmp eq i64 [[B:%.*]], [[C:%.*]] ; CHECK-NEXT: call void @foo() ; CHECK-NEXT: br label [[EXIT:%.*]] ; CHECK: bb1: ; CHECK-NEXT: [[TMP1:%.*]] = icmp eq i64 [[B]], [[C]] ; CHECK-NEXT: call void @foo() ; CHECK-NEXT: br label [[EXIT]] ; CHECK: bb2: ; CHECK-NEXT: [[TMP2:%.*]] = icmp eq i64 [[B]], [[C]] ; CHECK-NEXT: call void @foo() ; CHECK-NEXT: br label [[EXIT]] ; CHECK: exit: ; CHECK-NEXT: [[RESULT:%.*]] = phi i1 [ [[TMP0]], [[BB0]] ], [ [[TMP1]], [[BB1]] ], [ [[TMP2]], [[BB2]] ] ; CHECK-NEXT: ret i1 [[RESULT]] ; start: switch i64 %a, label %unreachable [ i64 0, label %bb0 i64 1, label %bb1 i64 2, label %bb2 ] unreachable: call void @no_return() unreachable bb0: ; preds = %start %0 = icmp eq i64 %b, %c call void @foo() br label %exit bb1: ; preds = %start %1 = icmp eq i64 %b, %c call void @foo() br label %exit bb2: ; preds = %start %2 = icmp eq i64 %b, %c call void @foo() br label %exit exit: ; preds = %bb2, %bb1, %bb0 %result = phi i1 [ %0, %bb0 ], [ %1, %bb1 ], [ %2, %bb2 ] ret i1 %result } ; If we can hoist a musttail call, ; we can and have to hoist subsequent bitcast and ret instructions. define ptr @switch_musttail_call(ptr %arg) { ; CHECK-LABEL: @switch_musttail_call( ; CHECK-NEXT: bb: ; CHECK-NEXT: [[P0:%.*]] = musttail call ptr @musttail_call(ptr [[ARG:%.*]]) ; CHECK-NEXT: ret ptr [[P0]] ; bb: %load = load i16, ptr %arg, align 2 switch i16 %load, label %unreachable [ i16 0, label %bb0 i16 1, label %bb1 i16 2, label %bb2 ] unreachable: unreachable bb0: %p0 = musttail call ptr @musttail_call(ptr %arg) ret ptr %p0 bb1: %p1 = musttail call ptr @musttail_call(ptr %arg) ret ptr %p1 bb2: %p2 = musttail call ptr @musttail_call(ptr %arg) ret ptr %p2 } declare void @no_return() declare void @foo() declare ptr @musttail_call(ptr)