; NOTE: Assertions have been autogenerated by utils/update_test_checks.py ; RUN: opt < %s -lowerswitch -S | FileCheck %s ; Check that we do not generate redundant comparisons that would have results ; known at compile time due to limited range of the value being switch'ed over. define i32 @test1(i32 %val) { ; CHECK-LABEL: @test1( ; CHECK-NEXT: entry: ; CHECK-NEXT: [[TRUNC:%.*]] = trunc i32 [[VAL:%.*]] to i2 ; CHECK-NEXT: br label [[NODEBLOCK:%.*]] ; CHECK: NodeBlock: ; CHECK-NEXT: [[PIVOT:%.*]] = icmp slt i2 [[TRUNC]], 1 ; CHECK-NEXT: br i1 [[PIVOT]], label [[LEAFBLOCK:%.*]], label [[CASE_1:%.*]] ; CHECK: LeafBlock: ; CHECK-NEXT: [[SWITCHLEAF:%.*]] = icmp eq i2 [[TRUNC]], -2 ; CHECK-NEXT: br i1 [[SWITCHLEAF]], label [[CASE_2:%.*]], label [[NEWDEFAULT:%.*]] ; CHECK: case.1: ; CHECK-NEXT: [[RES1:%.*]] = call i32 @case1() ; CHECK-NEXT: br label [[EXIT:%.*]] ; CHECK: case.2: ; CHECK-NEXT: [[RES2:%.*]] = call i32 @case2() ; CHECK-NEXT: br label [[EXIT]] ; CHECK: NewDefault: ; CHECK-NEXT: br label [[CASE_D:%.*]] ; CHECK: case.D: ; CHECK-NEXT: [[RESD:%.*]] = call i32 @caseD() ; CHECK-NEXT: br label [[EXIT]] ; CHECK: exit: ; CHECK-NEXT: [[RES:%.*]] = phi i32 [ [[RES1]], [[CASE_1]] ], [ [[RES2]], [[CASE_2]] ], [ [[RESD]], [[CASE_D]] ] ; CHECK-NEXT: ret i32 [[RES]] ; entry: %trunc = trunc i32 %val to i2 switch i2 %trunc, label %case.D [ i2 1, label %case.1 ; i2 1 i2 2, label %case.2 ; i2 -2 ] ; It's known that %val can not be less than -2 or greater than 1 case.1: %res1 = call i32 @case1() br label %exit case.2: %res2 = call i32 @case2() br label %exit case.D: %resD = call i32 @caseD() br label %exit exit: %res = phi i32 [ %res1, %case.1 ], [ %res2, %case.2 ], [ %resD, %case.D ] ret i32 %res } ; Check that we do not generate redundant comparisons that would have results ; known at compile time due to limited range of the value being switch'ed over. define i32 @test2() { ; CHECK-LABEL: @test2( ; CHECK-NEXT: entry: ; CHECK-NEXT: [[VAL:%.*]] = call i32 @getVal(), !range !0 ; CHECK-NEXT: br label [[NODEBLOCK:%.*]] ; CHECK: NodeBlock: ; CHECK-NEXT: [[PIVOT:%.*]] = icmp slt i32 [[VAL]], 2 ; CHECK-NEXT: br i1 [[PIVOT]], label [[CASE_1:%.*]], label [[LEAFBLOCK:%.*]] ; CHECK: LeafBlock: ; CHECK-NEXT: [[SWITCHLEAF:%.*]] = icmp eq i32 [[VAL]], 2 ; CHECK-NEXT: br i1 [[SWITCHLEAF]], label [[CASE_2:%.*]], label [[NEWDEFAULT:%.*]] ; CHECK: case.1: ; CHECK-NEXT: [[RES1:%.*]] = call i32 @case1() ; CHECK-NEXT: br label [[EXIT:%.*]] ; CHECK: case.2: ; CHECK-NEXT: [[RES2:%.*]] = call i32 @case2() ; CHECK-NEXT: br label [[EXIT]] ; CHECK: NewDefault: ; CHECK-NEXT: br label [[CASE_D:%.*]] ; CHECK: case.D: ; CHECK-NEXT: [[RESD:%.*]] = call i32 @caseD() ; CHECK-NEXT: br label [[EXIT]] ; CHECK: exit: ; CHECK-NEXT: [[RES:%.*]] = phi i32 [ [[RES1]], [[CASE_1]] ], [ [[RES2]], [[CASE_2]] ], [ [[RESD]], [[CASE_D]] ] ; CHECK-NEXT: ret i32 [[RES]] ; entry: %val = call i32 @getVal(), !range !0 switch i32 %val, label %case.D [ i32 1, label %case.1 i32 2, label %case.2 ] ; It's known that %val can not be less than 1 case.1: %res1 = call i32 @case1() br label %exit case.2: %res2 = call i32 @case2() br label %exit case.D: %resD = call i32 @caseD() br label %exit exit: %res = phi i32 [ %res1, %case.1 ], [ %res2, %case.2 ], [ %resD, %case.D ] ret i32 %res } ; Corner case: ; 1) some of the non-default cases are unreachable due to the !range constraint, ; 2) the default case is unreachable as non-default cases cover the range fully. define i32 @test3() { ; CHECK-LABEL: @test3( ; CHECK-NEXT: entry: ; CHECK-NEXT: [[VAL:%.*]] = call i32 @getVal(), !range !1 ; CHECK-NEXT: br label [[LEAFBLOCK:%.*]] ; CHECK: LeafBlock: ; CHECK-NEXT: [[SWITCHLEAF:%.*]] = icmp eq i32 [[VAL]], 2 ; CHECK-NEXT: br i1 [[SWITCHLEAF]], label [[CASE_2:%.*]], label [[NEWDEFAULT:%.*]] ; CHECK: NewDefault: ; CHECK-NEXT: br label [[CASE_1:%.*]] ; CHECK: case.1: ; CHECK-NEXT: [[RES1:%.*]] = call i32 @case1() ; CHECK-NEXT: br label [[EXIT:%.*]] ; CHECK: case.2: ; CHECK-NEXT: [[RES2:%.*]] = call i32 @case2() ; CHECK-NEXT: br label [[EXIT]] ; CHECK: exit: ; CHECK-NEXT: [[RES:%.*]] = phi i32 [ [[RES1]], [[CASE_1]] ], [ [[RES2]], [[CASE_2]] ] ; CHECK-NEXT: ret i32 [[RES]] ; entry: %val = call i32 @getVal(), !range !1 switch i32 %val, label %case.D [ i32 1, label %case.1 i32 2, label %case.2 i32 3, label %case.1 ] case.1: %res1 = call i32 @case1() br label %exit case.2: %res2 = call i32 @case2() br label %exit case.D: %resD = call i32 @caseD() br label %exit exit: %res = phi i32 [ %res1, %case.1 ], [ %res2, %case.2 ], [ %resD, %case.D ] ret i32 %res } ; Corner case: ; 1) some of the non-default cases are unreachable due to the !range constraint, ; 2) the default case is still reachable as non-default cases do not cover the ; range fully. define i32 @test4() { ; CHECK-LABEL: @test4( ; CHECK-NEXT: entry: ; CHECK-NEXT: [[VAL:%.*]] = call i32 @getVal(), !range !2 ; CHECK-NEXT: br label [[NODEBLOCK:%.*]] ; CHECK: NodeBlock: ; CHECK-NEXT: [[PIVOT:%.*]] = icmp slt i32 [[VAL]], 2 ; CHECK-NEXT: br i1 [[PIVOT]], label [[CASE_1:%.*]], label [[LEAFBLOCK:%.*]] ; CHECK: LeafBlock: ; CHECK-NEXT: [[SWITCHLEAF:%.*]] = icmp eq i32 [[VAL]], 2 ; CHECK-NEXT: br i1 [[SWITCHLEAF]], label [[CASE_2:%.*]], label [[NEWDEFAULT:%.*]] ; CHECK: case.1: ; CHECK-NEXT: [[RES1:%.*]] = call i32 @case1() ; CHECK-NEXT: br label [[EXIT:%.*]] ; CHECK: case.2: ; CHECK-NEXT: [[RES2:%.*]] = call i32 @case2() ; CHECK-NEXT: br label [[EXIT]] ; CHECK: NewDefault: ; CHECK-NEXT: br label [[CASE_D:%.*]] ; CHECK: case.D: ; CHECK-NEXT: [[RESD:%.*]] = call i32 @caseD() ; CHECK-NEXT: br label [[EXIT]] ; CHECK: exit: ; CHECK-NEXT: [[RES:%.*]] = phi i32 [ [[RES1]], [[CASE_1]] ], [ [[RES2]], [[CASE_2]] ], [ [[RESD]], [[CASE_D]] ] ; CHECK-NEXT: ret i32 [[RES]] ; entry: %val = call i32 @getVal(), !range !2 switch i32 %val, label %case.D [ i32 1, label %case.1 i32 2, label %case.2 ] case.1: %res1 = call i32 @case1() br label %exit case.2: %res2 = call i32 @case2() br label %exit case.D: %resD = call i32 @caseD() br label %exit exit: %res = phi i32 [ %res1, %case.1 ], [ %res2, %case.2 ], [ %resD, %case.D ] ret i32 %res } ; Corner case: ; 1) some of the non-default cases are unreachable due to the !range constraint, ; 2) the default case appears to be unreachable as non-default cases cover the ; range fully, but its basic block actually is reachable from the switch via ; one of the non-default cases. define i32 @test5(i1 %cond) { ; CHECK-LABEL: @test5( ; CHECK-NEXT: entry: ; CHECK-NEXT: br i1 [[COND:%.*]], label [[SWITCH:%.*]], label [[CASE_D:%.*]] ; CHECK: switch: ; CHECK-NEXT: [[VAL:%.*]] = call i32 @getVal(), !range !1 ; CHECK-NEXT: br label [[NODEBLOCK:%.*]] ; CHECK: NodeBlock: ; CHECK-NEXT: [[PIVOT:%.*]] = icmp slt i32 [[VAL]], 3 ; CHECK-NEXT: br i1 [[PIVOT]], label [[LEAFBLOCK:%.*]], label [[CASE_1:%.*]] ; CHECK: LeafBlock: ; CHECK-NEXT: [[SWITCHLEAF:%.*]] = icmp eq i32 [[VAL]], 1 ; CHECK-NEXT: br i1 [[SWITCHLEAF]], label [[CASE_1]], label [[NEWDEFAULT:%.*]] ; CHECK: case.1: ; CHECK-NEXT: [[RES1:%.*]] = call i32 @case1() ; CHECK-NEXT: br label [[EXIT:%.*]] ; CHECK: NewDefault: ; CHECK-NEXT: br label [[CASE_D]] ; CHECK: case.D: ; CHECK-NEXT: [[DELTA:%.*]] = phi i32 [ 0, [[ENTRY:%.*]] ], [ 20, [[NEWDEFAULT]] ] ; CHECK-NEXT: [[RESD_TMP:%.*]] = call i32 @caseD() ; CHECK-NEXT: [[RESD:%.*]] = add i32 [[RESD_TMP]], [[DELTA]] ; CHECK-NEXT: br label [[EXIT]] ; CHECK: exit: ; CHECK-NEXT: [[RES:%.*]] = phi i32 [ [[RES1]], [[CASE_1]] ], [ [[RESD]], [[CASE_D]] ] ; CHECK-NEXT: ret i32 [[RES]] ; entry: br i1 %cond, label %switch, label %case.D switch: %val = call i32 @getVal(), !range !1 switch i32 %val, label %case.D [ i32 1, label %case.1 i32 2, label %case.D i32 3, label %case.1 ] case.1: %res1 = call i32 @case1() br label %exit case.D: %delta = phi i32 [ 0, %entry ], [ 20, %switch ], [ 20, %switch ] %resD.tmp = call i32 @caseD() %resD = add i32 %resD.tmp, %delta br label %exit exit: %res = phi i32 [ %res1, %case.1 ], [ %resD, %case.D ] ret i32 %res } ; Corner case: ; 1) some of the non-default cases are unreachable due to the !range constraint, ; 2) the default case appears to be unreachable as non-default cases cover the ; range fully, but its basic block actually is reachable, though, from a ; different basic block, not the switch itself. define i32 @test6(i1 %cond) { ; CHECK-LABEL: @test6( ; CHECK-NEXT: entry: ; CHECK-NEXT: br i1 [[COND:%.*]], label [[SWITCH:%.*]], label [[CASE_D:%.*]] ; CHECK: switch: ; CHECK-NEXT: [[VAL:%.*]] = call i32 @getVal(), !range !1 ; CHECK-NEXT: br label [[LEAFBLOCK:%.*]] ; CHECK: LeafBlock: ; CHECK-NEXT: [[SWITCHLEAF:%.*]] = icmp eq i32 [[VAL]], 2 ; CHECK-NEXT: br i1 [[SWITCHLEAF]], label [[CASE_2:%.*]], label [[NEWDEFAULT:%.*]] ; CHECK: NewDefault: ; CHECK-NEXT: br label [[CASE_1:%.*]] ; CHECK: case.1: ; CHECK-NEXT: [[RES1:%.*]] = call i32 @case1() ; CHECK-NEXT: br label [[EXIT:%.*]] ; CHECK: case.2: ; CHECK-NEXT: [[RES2:%.*]] = call i32 @case2() ; CHECK-NEXT: br label [[EXIT]] ; CHECK: case.D: ; CHECK-NEXT: [[RESD_TMP:%.*]] = call i32 @caseD() ; CHECK-NEXT: [[RESD:%.*]] = add i32 [[RESD_TMP]], 0 ; CHECK-NEXT: br label [[EXIT]] ; CHECK: exit: ; CHECK-NEXT: [[RES:%.*]] = phi i32 [ [[RES1]], [[CASE_1]] ], [ [[RES2]], [[CASE_2]] ], [ [[RESD]], [[CASE_D]] ] ; CHECK-NEXT: ret i32 [[RES]] ; entry: br i1 %cond, label %switch, label %case.D switch: %val = call i32 @getVal(), !range !1 switch i32 %val, label %case.D [ i32 1, label %case.1 i32 2, label %case.2 i32 3, label %case.1 ] case.1: %res1 = call i32 @case1() br label %exit case.2: %res2 = call i32 @case2() br label %exit case.D: %delta = phi i32 [ 0, %entry ], [ 20, %switch ] %resD.tmp = call i32 @caseD() %resD = add i32 %resD.tmp, %delta br label %exit exit: %res = phi i32 [ %res1, %case.1 ], [ %res2, %case.2 ], [ %resD, %case.D ] ret i32 %res } ; Corner case: ; 1) switch appears to have a non-empty set of non-default cases, but all of ; them reference the default case basic block. define i32 @test7(i1 %cond) { ; CHECK-LABEL: @test7( ; CHECK-NEXT: entry: ; CHECK-NEXT: br i1 [[COND:%.*]], label [[SWITCH:%.*]], label [[CASE_D:%.*]] ; CHECK: switch: ; CHECK-NEXT: [[VAL:%.*]] = call i32 @getVal(), !range !1 ; CHECK-NEXT: br label [[CASE_D]] ; CHECK: case.D: ; CHECK-NEXT: [[DELTA:%.*]] = phi i32 [ 0, [[ENTRY:%.*]] ], [ 20, [[SWITCH]] ] ; CHECK-NEXT: [[RESD_TMP:%.*]] = call i32 @caseD() ; CHECK-NEXT: [[RESD:%.*]] = add i32 [[RESD_TMP]], [[DELTA]] ; CHECK-NEXT: br label [[EXIT:%.*]] ; CHECK: exit: ; CHECK-NEXT: ret i32 [[RESD]] ; entry: br i1 %cond, label %switch, label %case.D switch: %val = call i32 @getVal(), !range !1 switch i32 %val, label %case.D [ i32 2, label %case.D ] case.D: %delta = phi i32 [ 0, %entry ], [ 20, %switch ], [ 20, %switch ] %resD.tmp = call i32 @caseD() %resD = add i32 %resD.tmp, %delta br label %exit exit: ret i32 %resD } ; Corner case: ; 1) some of the non-default cases are unreachable due to the !range constraint, ; 2) the default case appears to be unreachable as non-default cases cover the ; range fully, but its basic block actually is reachable from the switch via ; one of the non-default cases, ; 3) such cases lie at the boundary of the range of values covered by ; non-default cases, and if removed, do not change the fact that the rest of ; the cases fully covers the value range. define i32 @test8(i1 %cond) { ; CHECK-LABEL: @test8( ; CHECK-NEXT: entry: ; CHECK-NEXT: br i1 [[COND:%.*]], label [[SWITCH:%.*]], label [[CASE_D:%.*]] ; CHECK: switch: ; CHECK-NEXT: [[VAL:%.*]] = call i32 @getVal(), !range !3 ; CHECK-NEXT: br label [[LEAFBLOCK:%.*]] ; CHECK: LeafBlock: ; CHECK-NEXT: [[SWITCHLEAF:%.*]] = icmp eq i32 [[VAL]], 2 ; CHECK-NEXT: br i1 [[SWITCHLEAF]], label [[CASE_2:%.*]], label [[NEWDEFAULT:%.*]] ; CHECK: NewDefault: ; CHECK-NEXT: br label [[CASE_1:%.*]] ; CHECK: case.1: ; CHECK-NEXT: [[RES1:%.*]] = call i32 @case1() ; CHECK-NEXT: br label [[EXIT:%.*]] ; CHECK: case.2: ; CHECK-NEXT: [[RES2:%.*]] = call i32 @case2() ; CHECK-NEXT: br label [[EXIT]] ; CHECK: case.D: ; CHECK-NEXT: [[RESD_TMP:%.*]] = call i32 @caseD() ; CHECK-NEXT: [[RESD:%.*]] = add i32 [[RESD_TMP]], 0 ; CHECK-NEXT: br label [[EXIT]] ; CHECK: exit: ; CHECK-NEXT: [[RES:%.*]] = phi i32 [ [[RES1]], [[CASE_1]] ], [ [[RES2]], [[CASE_2]] ], [ [[RESD]], [[CASE_D]] ] ; CHECK-NEXT: ret i32 [[RES]] ; entry: br i1 %cond, label %switch, label %case.D switch: %val = call i32 @getVal(), !range !3 switch i32 %val, label %case.D [ i32 1, label %case.1 i32 2, label %case.2 i32 3, label %case.D ] case.1: %res1 = call i32 @case1() br label %exit case.2: %res2 = call i32 @case2() br label %exit case.D: %delta = phi i32 [ 0, %entry ], [ 20, %switch ], [ 20, %switch ] %resD.tmp = call i32 @caseD() %resD = add i32 %resD.tmp, %delta br label %exit exit: %res = phi i32 [ %res1, %case.1 ], [ %res2, %case.2 ], [ %resD, %case.D ] ret i32 %res } ; Corner case: ; 1) the default case appears to be unreachable as non-default cases cover the ; range fully, but its basic block actually is reachable from the switch via ; more than one non-default case. define i32 @test9(i1 %cond, i2 %val) { ; CHECK-LABEL: @test9( ; CHECK-NEXT: entry: ; CHECK-NEXT: br i1 [[COND:%.*]], label [[SWITCH:%.*]], label [[CASE_D:%.*]] ; CHECK: switch: ; CHECK-NEXT: br label [[LEAFBLOCK:%.*]] ; CHECK: LeafBlock: ; CHECK-NEXT: [[SWITCHLEAF:%.*]] = icmp sge i2 [[VAL:%.*]], 0 ; CHECK-NEXT: br i1 [[SWITCHLEAF]], label [[CASE_1:%.*]], label [[NEWDEFAULT:%.*]] ; CHECK: case.1: ; CHECK-NEXT: [[RES1:%.*]] = call i32 @case1() ; CHECK-NEXT: br label [[EXIT:%.*]] ; CHECK: NewDefault: ; CHECK-NEXT: br label [[CASE_D]] ; CHECK: case.D: ; CHECK-NEXT: [[DELTA:%.*]] = phi i32 [ 20, [[NEWDEFAULT]] ], [ 0, [[ENTRY:%.*]] ] ; CHECK-NEXT: [[RESD_TMP:%.*]] = call i32 @caseD() ; CHECK-NEXT: [[RESD:%.*]] = add i32 [[RESD_TMP]], [[DELTA]] ; CHECK-NEXT: br label [[EXIT]] ; CHECK: exit: ; CHECK-NEXT: [[RES:%.*]] = phi i32 [ [[RES1]], [[CASE_1]] ], [ [[RESD]], [[CASE_D]] ] ; CHECK-NEXT: ret i32 [[RES]] ; entry: br i1 %cond, label %switch, label %case.D switch: switch i2 %val, label %case.D [ i2 0, label %case.1 i2 1, label %case.1 i2 2, label %case.D i2 3, label %case.D ] case.1: %res1 = call i32 @case1() br label %exit case.D: %delta = phi i32 [20, %switch ], [ 20, %switch ], [ 20, %switch ], [ 0, %entry ] %resD.tmp = call i32 @caseD() %resD = add i32 %resD.tmp, %delta br label %exit exit: %res = phi i32 [ %res1, %case.1 ], [ %resD, %case.D ] ret i32 %res } ; Check that we do not generate redundant comparisons that would have results ; known at compile time due to limited range of the value being switch'ed over. define i32 @test10() { ; CHECK-LABEL: @test10( ; CHECK-NEXT: entry: ; CHECK-NEXT: [[VAL:%.*]] = call i32 @getVal() ; CHECK-NEXT: [[COND_LEFT:%.*]] = icmp sge i32 [[VAL]], 1 ; CHECK-NEXT: [[COND_RIGHT:%.*]] = icmp sle i32 [[VAL]], 6 ; CHECK-NEXT: [[COND:%.*]] = and i1 [[COND_LEFT]], [[COND_RIGHT]] ; CHECK-NEXT: br i1 [[COND]], label [[SWITCH:%.*]], label [[CASE_D:%.*]] ; CHECK: switch: ; CHECK-NEXT: br label [[LEAFBLOCK:%.*]] ; CHECK: LeafBlock: ; CHECK-NEXT: [[VAL_OFF:%.*]] = add i32 [[VAL]], -3 ; CHECK-NEXT: [[SWITCHLEAF:%.*]] = icmp ule i32 [[VAL_OFF]], 1 ; CHECK-NEXT: br i1 [[SWITCHLEAF]], label [[CASE_2:%.*]], label [[NEWDEFAULT:%.*]] ; CHECK: NewDefault: ; CHECK-NEXT: br label [[CASE_1:%.*]] ; CHECK: case.1: ; CHECK-NEXT: [[RES1:%.*]] = call i32 @case1() ; CHECK-NEXT: br label [[EXIT:%.*]] ; CHECK: case.2: ; CHECK-NEXT: [[RES2:%.*]] = call i32 @case2() ; CHECK-NEXT: br label [[EXIT]] ; CHECK: case.D: ; CHECK-NEXT: br label [[EXIT]] ; CHECK: exit: ; CHECK-NEXT: [[RES:%.*]] = phi i32 [ [[RES1]], [[CASE_1]] ], [ [[RES2]], [[CASE_2]] ], [ 0, [[CASE_D]] ] ; CHECK-NEXT: ret i32 [[RES]] ; entry: %val = call i32 @getVal() %cond.left = icmp sge i32 %val, 1 %cond.right = icmp sle i32 %val, 6 %cond = and i1 %cond.left, %cond.right br i1 %cond, label %switch, label %case.D switch: switch i32 %val, label %case.D [ i32 1, label %case.1 i32 2, label %case.1 i32 3, label %case.2 i32 4, label %case.2 i32 5, label %case.1 i32 6, label %case.1 ] ; It's known that %val <- [1, 6] case.1: %res1 = call i32 @case1() br label %exit case.2: %res2 = call i32 @case2() br label %exit case.D: %resD = phi i32 [ 20, %switch ], [ 0, %entry ] br label %exit exit: %res = phi i32 [ %res1, %case.1 ], [ %res2, %case.2 ], [ %resD, %case.D ] ret i32 %res } ; Check that we do not generate redundant comparisons that would have results ; known at compile time due to limited range of the value being switch'ed over. define i32 @test11() { ; CHECK-LABEL: @test11( ; CHECK-NEXT: entry: ; CHECK-NEXT: [[VAL:%.*]] = call i32 @getVal() ; CHECK-NEXT: [[VAL_ZEXT:%.*]] = zext i32 [[VAL]] to i64 ; CHECK-NEXT: br label [[NODEBLOCK:%.*]] ; CHECK: NodeBlock: ; CHECK-NEXT: [[PIVOT:%.*]] = icmp slt i64 [[VAL_ZEXT]], 1 ; CHECK-NEXT: br i1 [[PIVOT]], label [[CASE_1:%.*]], label [[LEAFBLOCK:%.*]] ; CHECK: LeafBlock: ; CHECK-NEXT: [[SWITCHLEAF:%.*]] = icmp eq i64 [[VAL_ZEXT]], 1 ; CHECK-NEXT: br i1 [[SWITCHLEAF]], label [[CASE_2:%.*]], label [[NEWDEFAULT:%.*]] ; CHECK: case.1: ; CHECK-NEXT: [[RES1:%.*]] = call i32 @case1() ; CHECK-NEXT: br label [[EXIT:%.*]] ; CHECK: case.2: ; CHECK-NEXT: [[RES2:%.*]] = call i32 @case2() ; CHECK-NEXT: br label [[EXIT]] ; CHECK: NewDefault: ; CHECK-NEXT: br label [[CASE_D:%.*]] ; CHECK: case.D: ; CHECK-NEXT: [[RESD:%.*]] = call i32 @caseD() ; CHECK-NEXT: br label [[EXIT]] ; CHECK: exit: ; CHECK-NEXT: [[RES:%.*]] = phi i32 [ [[RES1]], [[CASE_1]] ], [ [[RES2]], [[CASE_2]] ], [ [[RESD]], [[CASE_D]] ] ; CHECK-NEXT: ret i32 [[RES]] ; entry: %val = call i32 @getVal() %val.zext = zext i32 %val to i64 switch i64 %val.zext, label %case.D [ i64 0, label %case.1 i64 1, label %case.2 ] ; It's known that %val can not be less than 0 case.1: %res1 = call i32 @case1() br label %exit case.2: %res2 = call i32 @case2() br label %exit case.D: %resD = call i32 @caseD() br label %exit exit: %res = phi i32 [ %res1, %case.1 ], [ %res2, %case.2 ], [ %resD, %case.D ] ret i32 %res } ; Check that we do not generate redundant comparisons that would have results ; known at compile time due to limited range of the value being switch'ed over. define void @test12() { ; CHECK-LABEL: @test12( ; CHECK-NEXT: entry: ; CHECK-NEXT: br label [[FOR_BODY:%.*]] ; CHECK: for.body: ; CHECK-NEXT: [[INDVAR:%.*]] = phi i32 [ 0, [[ENTRY:%.*]] ], [ [[INC:%.*]], [[LATCH:%.*]] ] ; CHECK-NEXT: br label [[NODEBLOCK:%.*]] ; CHECK: NodeBlock: ; CHECK-NEXT: [[PIVOT:%.*]] = icmp slt i32 [[INDVAR]], 1 ; CHECK-NEXT: br i1 [[PIVOT]], label [[CASE_1:%.*]], label [[LEAFBLOCK:%.*]] ; CHECK: LeafBlock: ; CHECK-NEXT: [[SWITCHLEAF:%.*]] = icmp eq i32 [[INDVAR]], 1 ; CHECK-NEXT: br i1 [[SWITCHLEAF]], label [[CASE_2:%.*]], label [[NEWDEFAULT:%.*]] ; CHECK: case.1: ; CHECK-NEXT: br label [[LATCH]] ; CHECK: case.2: ; CHECK-NEXT: br label [[LATCH]] ; CHECK: NewDefault: ; CHECK-NEXT: br label [[LATCH]] ; CHECK: latch: ; CHECK-NEXT: [[INC]] = add nuw nsw i32 [[INDVAR]], 1 ; CHECK-NEXT: br i1 undef, label [[EXIT:%.*]], label [[FOR_BODY]] ; CHECK: exit: ; CHECK-NEXT: ret void ; entry: br label %for.body for.body: %indvar = phi i32 [ 0, %entry ], [ %inc, %latch ] switch i32 %indvar, label %latch [ i32 0, label %case.1 i32 1, label %case.2 ] ; It's known that %indvar can not be less than 0 case.1: br label %latch case.2: br label %latch latch: %inc = add nuw nsw i32 %indvar, 1 br i1 undef, label %exit, label %for.body exit: ret void } ; Check that we do not generate redundant comparisons that would have results ; known at compile time due to limited range of the value being switch'ed over. define void @test13(i32 %val) { ; CHECK-LABEL: @test13( ; CHECK-NEXT: entry: ; CHECK-NEXT: [[TMP:%.*]] = and i32 [[VAL:%.*]], 7 ; CHECK-NEXT: br label [[BB33:%.*]] ; CHECK: bb33: ; CHECK-NEXT: br label [[LEAFBLOCK:%.*]] ; CHECK: LeafBlock: ; CHECK-NEXT: [[TMP_OFF:%.*]] = add i32 [[TMP]], -2 ; CHECK-NEXT: [[SWITCHLEAF:%.*]] = icmp ule i32 [[TMP_OFF]], 1 ; CHECK-NEXT: br i1 [[SWITCHLEAF]], label [[BB34:%.*]], label [[NEWDEFAULT:%.*]] ; CHECK: bb34: ; CHECK-NEXT: br label [[BB38:%.*]] ; CHECK: NewDefault: ; CHECK-NEXT: br label [[BB35:%.*]] ; CHECK: bb35: ; CHECK-NEXT: br label [[NODEBLOCK:%.*]] ; CHECK: NodeBlock: ; CHECK-NEXT: [[PIVOT:%.*]] = icmp slt i32 [[TMP]], 6 ; CHECK-NEXT: br i1 [[PIVOT]], label [[LEAFBLOCK2:%.*]], label [[BB37:%.*]] ; CHECK: LeafBlock2: ; CHECK-NEXT: [[SWITCHLEAF3:%.*]] = icmp sle i32 [[TMP]], 1 ; CHECK-NEXT: br i1 [[SWITCHLEAF3]], label [[BB37]], label [[NEWDEFAULT1:%.*]] ; CHECK: bb37: ; CHECK-NEXT: br label [[BB38]] ; CHECK: NewDefault1: ; CHECK-NEXT: br label [[BB38]] ; CHECK: bb38: ; CHECK-NEXT: br label [[BB33]] ; entry: %tmp = and i32 %val, 7 br label %bb33 bb33: switch i32 %tmp, label %bb35 [ i32 2, label %bb34 i32 3, label %bb34 ] bb34: br label %bb38 bb35: switch i32 %tmp, label %bb38 [ i32 0, label %bb37 i32 1, label %bb37 i32 6, label %bb37 i32 7, label %bb37 ] ; It's known that %tmp <- [0, 1] U [4, 7] bb37: br label %bb38 bb38: br label %bb33 } ; Check that we do not generate redundant comparisons that would have results ; known at compile time due to limited range of the value being switch'ed over. define i32 @test14() { ; CHECK-LABEL: @test14( ; CHECK-NEXT: entry: ; CHECK-NEXT: [[TMP:%.*]] = call i32 @getVal(), !range !4 ; CHECK-NEXT: [[VAL:%.*]] = call i32 @llvm.ctpop.i32(i32 [[TMP]]) ; CHECK-NEXT: br label [[NODEBLOCK:%.*]] ; CHECK: NodeBlock: ; CHECK-NEXT: [[PIVOT:%.*]] = icmp slt i32 [[VAL]], 1 ; CHECK-NEXT: br i1 [[PIVOT]], label [[CASE_1:%.*]], label [[LEAFBLOCK:%.*]] ; CHECK: LeafBlock: ; CHECK-NEXT: [[SWITCHLEAF:%.*]] = icmp eq i32 [[VAL]], 1 ; CHECK-NEXT: br i1 [[SWITCHLEAF]], label [[CASE_2:%.*]], label [[NEWDEFAULT:%.*]] ; CHECK: case.1: ; CHECK-NEXT: [[RES1:%.*]] = call i32 @case1() ; CHECK-NEXT: br label [[EXIT:%.*]] ; CHECK: case.2: ; CHECK-NEXT: [[RES2:%.*]] = call i32 @case2() ; CHECK-NEXT: br label [[EXIT]] ; CHECK: NewDefault: ; CHECK-NEXT: br label [[CASE_D:%.*]] ; CHECK: case.D: ; CHECK-NEXT: [[RESD:%.*]] = call i32 @caseD() ; CHECK-NEXT: br label [[EXIT]] ; CHECK: exit: ; CHECK-NEXT: [[RES:%.*]] = phi i32 [ [[RES1]], [[CASE_1]] ], [ [[RES2]], [[CASE_2]] ], [ [[RESD]], [[CASE_D]] ] ; CHECK-NEXT: ret i32 [[RES]] ; entry: %tmp = call i32 @getVal(), !range !4 %val = call i32 @llvm.ctpop.i32(i32 %tmp) switch i32 %val, label %case.D [ i32 0, label %case.1 i32 1, label %case.2 ] ; It's known that %val <- [0, 2] case.1: %res1 = call i32 @case1() br label %exit case.2: %res2 = call i32 @case2() br label %exit case.D: %resD = call i32 @caseD() br label %exit exit: %res = phi i32 [ %res1, %case.1 ], [ %res2, %case.2 ], [ %resD, %case.D ] ret i32 %res } ; Check that we do not generate redundant comparisons that would have results ; known at compile time due to limited range of the value being switch'ed over. define i32 @test15() { ; CHECK-LABEL: @test15( ; CHECK-NEXT: entry: ; CHECK-NEXT: [[TMP:%.*]] = call i32 @getVal() ; CHECK-NEXT: [[VAL:%.*]] = urem i32 [[TMP]], 3 ; CHECK-NEXT: br label [[NODEBLOCK:%.*]] ; CHECK: NodeBlock: ; CHECK-NEXT: [[PIVOT:%.*]] = icmp slt i32 [[VAL]], 1 ; CHECK-NEXT: br i1 [[PIVOT]], label [[CASE_1:%.*]], label [[LEAFBLOCK:%.*]] ; CHECK: LeafBlock: ; CHECK-NEXT: [[SWITCHLEAF:%.*]] = icmp eq i32 [[VAL]], 1 ; CHECK-NEXT: br i1 [[SWITCHLEAF]], label [[CASE_2:%.*]], label [[NEWDEFAULT:%.*]] ; CHECK: case.1: ; CHECK-NEXT: [[RES1:%.*]] = call i32 @case1() ; CHECK-NEXT: br label [[EXIT:%.*]] ; CHECK: case.2: ; CHECK-NEXT: [[RES2:%.*]] = call i32 @case2() ; CHECK-NEXT: br label [[EXIT]] ; CHECK: NewDefault: ; CHECK-NEXT: br label [[CASE_D:%.*]] ; CHECK: case.D: ; CHECK-NEXT: [[RESD:%.*]] = call i32 @caseD() ; CHECK-NEXT: br label [[EXIT]] ; CHECK: exit: ; CHECK-NEXT: [[RES:%.*]] = phi i32 [ [[RES1]], [[CASE_1]] ], [ [[RES2]], [[CASE_2]] ], [ [[RESD]], [[CASE_D]] ] ; CHECK-NEXT: ret i32 [[RES]] ; entry: %tmp = call i32 @getVal() %val = urem i32 %tmp, 3 switch i32 %val, label %case.D [ i32 0, label %case.1 i32 1, label %case.2 ] ; It's known that %val <- [0, 2] case.1: %res1 = call i32 @case1() br label %exit case.2: %res2 = call i32 @case2() br label %exit case.D: %resD = call i32 @caseD() br label %exit exit: %res = phi i32 [ %res1, %case.1 ], [ %res2, %case.2 ], [ %resD, %case.D ] ret i32 %res } ; Check that we do not generate redundant comparisons that would have results ; known at compile time due to limited range of the value being switch'ed over. define i32 @test16(float %f) { ; CHECK-LABEL: @test16( ; CHECK-NEXT: entry: ; CHECK-NEXT: [[I:%.*]] = fptosi float [[F:%.*]] to i64 ; CHECK-NEXT: [[COND_LEFT:%.*]] = icmp slt i64 [[I]], 0 ; CHECK-NEXT: [[CLAMP_LEFT:%.*]] = select i1 [[COND_LEFT]], i64 0, i64 [[I]] ; CHECK-NEXT: [[COND_RIGHT:%.*]] = icmp sgt i64 [[I]], 3 ; CHECK-NEXT: [[CLAMP:%.*]] = select i1 [[COND_RIGHT]], i64 3, i64 [[CLAMP_LEFT]] ; CHECK-NEXT: br label [[LEAFBLOCK:%.*]] ; CHECK: LeafBlock: ; CHECK-NEXT: [[SWITCHLEAF:%.*]] = icmp sge i64 [[CLAMP]], 2 ; CHECK-NEXT: br i1 [[SWITCHLEAF]], label [[CASE_2:%.*]], label [[NEWDEFAULT:%.*]] ; CHECK: NewDefault: ; CHECK-NEXT: br label [[CASE_1:%.*]] ; CHECK: case.1: ; CHECK-NEXT: [[RES1:%.*]] = call i32 @case1() ; CHECK-NEXT: br label [[EXIT:%.*]] ; CHECK: case.2: ; CHECK-NEXT: [[RES2:%.*]] = call i32 @case2() ; CHECK-NEXT: br label [[EXIT]] ; CHECK: exit: ; CHECK-NEXT: [[RES:%.*]] = phi i32 [ [[RES1]], [[CASE_1]] ], [ [[RES2]], [[CASE_2]] ] ; CHECK-NEXT: ret i32 [[RES]] ; entry: %i = fptosi float %f to i64 %cond.left = icmp slt i64 %i, 0 %clamp.left = select i1 %cond.left, i64 0, i64 %i %cond.right = icmp sgt i64 %i, 3 %clamp = select i1 %cond.right, i64 3, i64 %clamp.left switch i64 %clamp, label %case.D [ i64 0, label %case.1 i64 1, label %case.1 i64 2, label %case.2 i64 3, label %case.2 ] ; It's known that %val <- [0, 3] case.1: %res1 = call i32 @case1() br label %exit case.2: %res2 = call i32 @case2() br label %exit case.D: %resD = call i32 @caseD() br label %exit exit: %res = phi i32 [ %res1, %case.1 ], [ %res2, %case.2 ], [ %resD, %case.D ] ret i32 %res } declare i32 @case1() declare i32 @case2() declare i32 @caseD() declare i32 @getVal() declare i32 @llvm.ctpop.i32(i32) !0 = !{i32 1, i32 257} !1 = !{i32 2, i32 3} !2 = !{i32 2, i32 257} !3 = !{i32 1, i32 3} !4 = !{i32 0, i32 4}