1; NOTE: Assertions have been autogenerated by utils/update_test_checks.py 2; RUN: opt < %s -simplifycfg -simplifycfg-require-and-preserve-domtree=1 -forward-switch-cond=false -switch-range-to-icmp -S | FileCheck %s --check-prefix=NO_FWD 3; RUN: opt < %s -simplifycfg -simplifycfg-require-and-preserve-domtree=1 -forward-switch-cond=true -switch-range-to-icmp -S | FileCheck %s --check-prefix=FWD 4 5; RUN: opt < %s -passes='simplifycfg<no-forward-switch-cond;switch-range-to-icmp>' -S | FileCheck %s --check-prefix=NO_FWD 6; RUN: opt < %s -passes='simplifycfg<forward-switch-cond;switch-range-to-icmp>' -S | FileCheck %s --check-prefix=FWD 7 8; PR10131 9 10target datalayout = "e-p:32:32:32-i1:8:8-i8:8:8-i16:16:16-i32:32:32-i64:32:64-f32:32:32-f64:32:64-v64:64:64-v128:128:128-a0:0:64-f80:32:32-n8:16:32" 11target triple = "i386-pc-linux-gnu" 12 13define i32 @t(i32 %m) nounwind readnone { 14; NO_FWD-LABEL: @t( 15; NO_FWD-NEXT: entry: 16; NO_FWD-NEXT: switch i32 [[M:%.*]], label [[SW_BB4:%.*]] [ 17; NO_FWD-NEXT: i32 0, label [[RETURN:%.*]] 18; NO_FWD-NEXT: i32 1, label [[SW_BB1:%.*]] 19; NO_FWD-NEXT: i32 2, label [[SW_BB2:%.*]] 20; NO_FWD-NEXT: i32 3, label [[SW_BB3:%.*]] 21; NO_FWD-NEXT: ] 22; NO_FWD: sw.bb1: 23; NO_FWD-NEXT: br label [[RETURN]] 24; NO_FWD: sw.bb2: 25; NO_FWD-NEXT: br label [[RETURN]] 26; NO_FWD: sw.bb3: 27; NO_FWD-NEXT: br label [[RETURN]] 28; NO_FWD: sw.bb4: 29; NO_FWD-NEXT: br label [[RETURN]] 30; NO_FWD: return: 31; NO_FWD-NEXT: [[RETVAL_0:%.*]] = phi i32 [ 4, [[SW_BB4]] ], [ 3, [[SW_BB3]] ], [ 2, [[SW_BB2]] ], [ 1, [[SW_BB1]] ], [ 0, [[ENTRY:%.*]] ] 32; NO_FWD-NEXT: ret i32 [[RETVAL_0]] 33; 34; FWD-LABEL: @t( 35; FWD-NEXT: entry: 36; FWD-NEXT: [[SWITCH:%.*]] = icmp ult i32 [[M:%.*]], 4 37; FWD-NEXT: [[SPEC_SELECT:%.*]] = select i1 [[SWITCH]], i32 [[M]], i32 4 38; FWD-NEXT: ret i32 [[SPEC_SELECT]] 39; 40entry: 41 switch i32 %m, label %sw.bb4 [ 42 i32 0, label %sw.bb0 43 i32 1, label %sw.bb1 44 i32 2, label %sw.bb2 45 i32 3, label %sw.bb3 46 ] 47 48sw.bb0: ; preds = %entry 49 br label %return 50 51sw.bb1: ; preds = %entry 52 br label %return 53 54sw.bb2: ; preds = %entry 55 br label %return 56 57sw.bb3: ; preds = %entry 58 br label %return 59 60sw.bb4: ; preds = %entry 61 br label %return 62 63return: ; preds = %entry, %sw.bb4, %sw.bb3, %sw.bb2, %sw.bb1 64 %retval.0 = phi i32 [ 4, %sw.bb4 ], [ 3, %sw.bb3 ], [ 2, %sw.bb2 ], [ 1, %sw.bb1 ], [ 0, %sw.bb0 ] 65 ret i32 %retval.0 66} 67 68; If 1 incoming phi value is a case constant of a switch, convert it to the switch condition: 69; https://bugs.llvm.org/show_bug.cgi?id=34471 70; This then subsequently should allow squashing of the other trivial case blocks. 71 72define i32 @PR34471(i32 %x) { 73; NO_FWD-LABEL: @PR34471( 74; NO_FWD-NEXT: entry: 75; NO_FWD-NEXT: switch i32 [[X:%.*]], label [[ELSE3:%.*]] [ 76; NO_FWD-NEXT: i32 17, label [[RETURN:%.*]] 77; NO_FWD-NEXT: i32 19, label [[IF19:%.*]] 78; NO_FWD-NEXT: i32 42, label [[IF42:%.*]] 79; NO_FWD-NEXT: ] 80; NO_FWD: if19: 81; NO_FWD-NEXT: br label [[RETURN]] 82; NO_FWD: if42: 83; NO_FWD-NEXT: br label [[RETURN]] 84; NO_FWD: else3: 85; NO_FWD-NEXT: br label [[RETURN]] 86; NO_FWD: return: 87; NO_FWD-NEXT: [[R:%.*]] = phi i32 [ [[X]], [[IF19]] ], [ [[X]], [[IF42]] ], [ 0, [[ELSE3]] ], [ 17, [[ENTRY:%.*]] ] 88; NO_FWD-NEXT: ret i32 [[R]] 89; 90; FWD-LABEL: @PR34471( 91; FWD-NEXT: entry: 92; FWD-NEXT: switch i32 [[X:%.*]], label [[ELSE3:%.*]] [ 93; FWD-NEXT: i32 17, label [[RETURN:%.*]] 94; FWD-NEXT: i32 19, label [[RETURN]] 95; FWD-NEXT: i32 42, label [[RETURN]] 96; FWD-NEXT: ] 97; FWD: else3: 98; FWD-NEXT: br label [[RETURN]] 99; FWD: return: 100; FWD-NEXT: [[R:%.*]] = phi i32 [ 0, [[ELSE3]] ], [ [[X]], [[ENTRY:%.*]] ], [ [[X]], [[ENTRY]] ], [ [[X]], [[ENTRY]] ] 101; FWD-NEXT: ret i32 [[R]] 102; 103entry: 104 switch i32 %x, label %else3 [ 105 i32 17, label %return 106 i32 19, label %if19 107 i32 42, label %if42 108 ] 109 110if19: 111 br label %return 112 113if42: 114 br label %return 115 116else3: 117 br label %return 118 119return: 120 %r = phi i32 [ %x, %if19 ], [ %x, %if42 ], [ 0, %else3 ], [ 17, %entry ] 121 ret i32 %r 122} 123 124