; NOTE: Assertions have been autogenerated by utils/update_test_checks.py ; RUN: opt -passes=instcombine -S < %s | FileCheck %s declare void @use(i1) ; Check that we fold the condition of branches of the ; form: br dest1, dest2, where dest1 == dest2. define i32 @test(i32 %x) { ; CHECK-LABEL: @test( ; CHECK-NEXT: entry: ; CHECK-NEXT: br i1 false, label [[MERGE:%.*]], label [[MERGE]] ; CHECK: merge: ; CHECK-NEXT: ret i32 [[X:%.*]] ; entry: %cmp = icmp ult i32 %x, 7 br i1 %cmp, label %merge, label %merge merge: ret i32 %x } @global = global i8 0 define i32 @pat(i32 %x) { ; CHECK-LABEL: @pat( ; CHECK-NEXT: br i1 false, label [[PATATINO:%.*]], label [[PATATINO]] ; CHECK: patatino: ; CHECK-NEXT: ret i32 [[X:%.*]] ; %y = icmp eq i32 27, ptrtoint(ptr @global to i32) br i1 %y, label %patatino, label %patatino patatino: ret i32 %x } define i1 @test01(i1 %cond) { ; CHECK-LABEL: @test01( ; CHECK-NEXT: entry: ; CHECK-NEXT: br i1 [[COND:%.*]], label [[IF_TRUE_1:%.*]], label [[IF_FALSE_1:%.*]] ; CHECK: if.true.1: ; CHECK-NEXT: br label [[MERGE_1:%.*]] ; CHECK: if.false.1: ; CHECK-NEXT: br label [[MERGE_1]] ; CHECK: merge.1: ; CHECK-NEXT: br i1 [[COND]], label [[IF_TRUE_2:%.*]], label [[IF_FALSE_2:%.*]] ; CHECK: if.true.2: ; CHECK-NEXT: br label [[MERGE_2:%.*]] ; CHECK: if.false.2: ; CHECK-NEXT: br label [[MERGE_2]] ; CHECK: merge.2: ; CHECK-NEXT: ret i1 [[COND]] ; entry: br i1 %cond, label %if.true.1, label %if.false.1 if.true.1: br label %merge.1 if.false.1: br label %merge.1 merge.1: %merge.cond.1 = phi i1 [true, %if.true.1], [false, %if.false.1] br i1 %merge.cond.1, label %if.true.2, label %if.false.2 if.true.2: br label %merge.2 if.false.2: br label %merge.2 merge.2: %merge.cond.2 = phi i1 [true, %if.true.2], [false, %if.false.2] ret i1 %merge.cond.2 } define i1 @test02(i1 %cond) { ; CHECK-LABEL: @test02( ; CHECK-NEXT: entry: ; CHECK-NEXT: br i1 [[COND:%.*]], label [[IF_TRUE_1:%.*]], label [[IF_FALSE_1:%.*]] ; CHECK: if.true.1: ; CHECK-NEXT: br label [[MERGE_1:%.*]] ; CHECK: if.false.1: ; CHECK-NEXT: br label [[MERGE_1]] ; CHECK: merge.1: ; CHECK-NEXT: br i1 [[COND]], label [[IF_FALSE_2:%.*]], label [[IF_TRUE_2:%.*]] ; CHECK: if.true.2: ; CHECK-NEXT: br label [[MERGE_2:%.*]] ; CHECK: if.false.2: ; CHECK-NEXT: br label [[MERGE_2]] ; CHECK: merge.2: ; CHECK-NEXT: ret i1 [[COND]] ; entry: br i1 %cond, label %if.true.1, label %if.false.1 if.true.1: br label %merge.1 if.false.1: br label %merge.1 merge.1: %merge.cond.1 = phi i1 [false, %if.true.1], [true, %if.false.1] br i1 %merge.cond.1, label %if.true.2, label %if.false.2 if.true.2: br label %merge.2 if.false.2: br label %merge.2 merge.2: %merge.cond.2 = phi i1 [false, %if.true.2], [true, %if.false.2] ret i1 %merge.cond.2 } ; if (x && !y) ret 42; ret 3 --> if (!x || y) ret 3; ret 42 define i32 @logical_and_not(i1 %x, i1 %y) { ; CHECK-LABEL: @logical_and_not( ; CHECK-NEXT: entry: ; CHECK-NEXT: [[NOT_X:%.*]] = xor i1 [[X:%.*]], true ; CHECK-NEXT: [[TMP0:%.*]] = select i1 [[NOT_X]], i1 true, i1 [[Y:%.*]] ; CHECK-NEXT: br i1 [[TMP0]], label [[F:%.*]], label [[T:%.*]] ; CHECK: t: ; CHECK-NEXT: ret i32 42 ; CHECK: f: ; CHECK-NEXT: ret i32 3 ; entry: %noty = xor i1 %y, true %and = select i1 %x, i1 %noty, i1 false br i1 %and, label %t, label %f t: ret i32 42 f: ret i32 3 } ; if (x && y || !x) ret 3; ret 42 --> if (!x || y) ret 3; ret 42 define i32 @logical_and_or(i1 %x, i1 %y) { ; CHECK-LABEL: @logical_and_or( ; CHECK-NEXT: entry: ; CHECK-NEXT: [[NOT_X:%.*]] = xor i1 [[X:%.*]], true ; CHECK-NEXT: [[AND:%.*]] = select i1 [[NOT_X]], i1 true, i1 [[Y:%.*]] ; CHECK-NEXT: br i1 [[AND]], label [[F:%.*]], label [[T:%.*]] ; CHECK: t: ; CHECK-NEXT: ret i32 42 ; CHECK: f: ; CHECK-NEXT: ret i32 3 ; entry: %and = select i1 %x, i1 %y, i1 true br i1 %and, label %f, label %t t: ret i32 42 f: ret i32 3 } ; if (!x || y) ret 3; ret 42 define i32 @logical_or_not(i1 %x, i1 %y) { ; CHECK-LABEL: @logical_or_not( ; CHECK-NEXT: entry: ; CHECK-NEXT: [[NOTX:%.*]] = xor i1 [[X:%.*]], true ; CHECK-NEXT: [[AND:%.*]] = select i1 [[NOTX]], i1 true, i1 [[Y:%.*]] ; CHECK-NEXT: br i1 [[AND]], label [[F:%.*]], label [[T:%.*]] ; CHECK: t: ; CHECK-NEXT: ret i32 42 ; CHECK: f: ; CHECK-NEXT: ret i32 3 ; entry: %notx = xor i1 %x, true %and = select i1 %notx, i1 true, i1 %y br i1 %and, label %f, label %t t: ret i32 42 f: ret i32 3 } ; negative test define i32 @logical_and_not_use1(i1 %x, i1 %y) { ; CHECK-LABEL: @logical_and_not_use1( ; CHECK-NEXT: entry: ; CHECK-NEXT: [[NOTY:%.*]] = xor i1 [[Y:%.*]], true ; CHECK-NEXT: call void @use(i1 [[NOTY]]) ; CHECK-NEXT: [[AND:%.*]] = select i1 [[X:%.*]], i1 [[NOTY]], i1 false ; CHECK-NEXT: br i1 [[AND]], label [[T:%.*]], label [[F:%.*]] ; CHECK: t: ; CHECK-NEXT: ret i32 42 ; CHECK: f: ; CHECK-NEXT: ret i32 3 ; entry: %noty = xor i1 %y, true call void @use(i1 %noty) %and = select i1 %x, i1 %noty, i1 false br i1 %and, label %t, label %f t: ret i32 42 f: ret i32 3 } ; negative test define i32 @logical_and_not_use2(i1 %x, i1 %y) { ; CHECK-LABEL: @logical_and_not_use2( ; CHECK-NEXT: entry: ; CHECK-NEXT: [[NOTY:%.*]] = xor i1 [[Y:%.*]], true ; CHECK-NEXT: [[AND:%.*]] = select i1 [[X:%.*]], i1 [[NOTY]], i1 false ; CHECK-NEXT: call void @use(i1 [[AND]]) ; CHECK-NEXT: br i1 [[AND]], label [[T:%.*]], label [[F:%.*]] ; CHECK: t: ; CHECK-NEXT: ret i32 42 ; CHECK: f: ; CHECK-NEXT: ret i32 3 ; entry: %noty = xor i1 %y, true %and = select i1 %x, i1 %noty, i1 false call void @use(i1 %and) br i1 %and, label %t, label %f t: ret i32 42 f: ret i32 3 }