; RUN: opt < %s -simplifycfg -S -mtriple=x86_64-unknown-linux-gnu | FileCheck %s target datalayout = "e-p:64:64:64-i1:8:8-i8:8:8-i16:16:16-i32:32:32-i64:64:64-f32:32:32-f64:64:64-v64:64:64-v128:128:128-a0:0:64-s0:64:64-f80:128:128-n8:16:32:64-S128" target triple = "x86_64-unknown-linux-gnu" ; The table for @f ; CHECK: @switch.table = private unnamed_addr constant [7 x i32] [i32 55, i32 123, i32 0, i32 -1, i32 27, i32 62, i32 1] ; The float table for @h ; CHECK: @switch.table.1 = private unnamed_addr constant [4 x float] [float 0x40091EB860000000, float 0x3FF3BE76C0000000, float 0x4012449BA0000000, float 0x4001AE1480000000] ; The table for @foostring ; CHECK: @switch.table.2 = private unnamed_addr constant [4 x i8*] [i8* getelementptr inbounds ([4 x i8], [4 x i8]* @.str, i64 0, i64 0), i8* getelementptr inbounds ([4 x i8], [4 x i8]* @.str1, i64 0, i64 0), i8* getelementptr inbounds ([4 x i8], [4 x i8]* @.str2, i64 0, i64 0), i8* getelementptr inbounds ([4 x i8], [4 x i8]* @.str3, i64 0, i64 0)] ; The table for @earlyreturncrash ; CHECK: @switch.table.3 = private unnamed_addr constant [4 x i32] [i32 42, i32 9, i32 88, i32 5] ; The table for @large. ; CHECK: @switch.table.4 = private unnamed_addr constant [199 x i32] [i32 1, i32 4, i32 9, ; The table for @cprop ; CHECK: @switch.table.5 = private unnamed_addr constant [7 x i32] [i32 5, i32 42, i32 126, i32 -452, i32 128, i32 6, i32 7] ; The table for @unreachable_case ; CHECK: @switch.table.6 = private unnamed_addr constant [9 x i32] [i32 0, i32 0, i32 0, i32 2, i32 -1, i32 1, i32 1, i32 1, i32 1] ; A simple int-to-int selection switch. ; It is dense enough to be replaced by table lookup. ; The result is directly by a ret from an otherwise empty bb, ; so we return early, directly from the lookup bb. define i32 @f(i32 %c) { entry: switch i32 %c, label %sw.default [ i32 42, label %return i32 43, label %sw.bb1 i32 44, label %sw.bb2 i32 45, label %sw.bb3 i32 46, label %sw.bb4 i32 47, label %sw.bb5 i32 48, label %sw.bb6 ] sw.bb1: br label %return sw.bb2: br label %return sw.bb3: br label %return sw.bb4: br label %return sw.bb5: br label %return sw.bb6: br label %return sw.default: br label %return return: %retval.0 = phi i32 [ 15, %sw.default ], [ 1, %sw.bb6 ], [ 62, %sw.bb5 ], [ 27, %sw.bb4 ], [ -1, %sw.bb3 ], [ 0, %sw.bb2 ], [ 123, %sw.bb1 ], [ 55, %entry ] ret i32 %retval.0 ; CHECK-LABEL: @f( ; CHECK: entry: ; CHECK-NEXT: %switch.tableidx = sub i32 %c, 42 ; CHECK-NEXT: %0 = icmp ult i32 %switch.tableidx, 7 ; CHECK-NEXT: br i1 %0, label %switch.lookup, label %return ; CHECK: switch.lookup: ; CHECK-NEXT: %switch.gep = getelementptr inbounds [7 x i32], [7 x i32]* @switch.table, i32 0, i32 %switch.tableidx ; CHECK-NEXT: %switch.load = load i32, i32* %switch.gep ; CHECK-NEXT: ret i32 %switch.load ; CHECK: return: ; CHECK-NEXT: ret i32 15 } ; A switch used to initialize two variables, an i8 and a float. declare void @dummy(i8 signext, float) define void @h(i32 %x) { entry: switch i32 %x, label %sw.default [ i32 0, label %sw.epilog i32 1, label %sw.bb1 i32 2, label %sw.bb2 i32 3, label %sw.bb3 ] sw.bb1: br label %sw.epilog sw.bb2: br label %sw.epilog sw.bb3: br label %sw.epilog sw.default: br label %sw.epilog sw.epilog: %a.0 = phi i8 [ 7, %sw.default ], [ 5, %sw.bb3 ], [ 88, %sw.bb2 ], [ 9, %sw.bb1 ], [ 42, %entry ] %b.0 = phi float [ 0x4023FAE140000000, %sw.default ], [ 0x4001AE1480000000, %sw.bb3 ], [ 0x4012449BA0000000, %sw.bb2 ], [ 0x3FF3BE76C0000000, %sw.bb1 ], [ 0x40091EB860000000, %entry ] call void @dummy(i8 signext %a.0, float %b.0) ret void ; CHECK-LABEL: @h( ; CHECK: entry: ; CHECK-NEXT: %switch.tableidx = sub i32 %x, 0 ; CHECK-NEXT: %0 = icmp ult i32 %switch.tableidx, 4 ; CHECK-NEXT: br i1 %0, label %switch.lookup, label %sw.epilog ; CHECK: switch.lookup: ; CHECK-NEXT: %switch.shiftamt = mul i32 %switch.tableidx, 8 ; CHECK-NEXT: %switch.downshift = lshr i32 89655594, %switch.shiftamt ; CHECK-NEXT: %switch.masked = trunc i32 %switch.downshift to i8 ; CHECK-NEXT: %switch.gep = getelementptr inbounds [4 x float], [4 x float]* @switch.table.1, i32 0, i32 %switch.tableidx ; CHECK-NEXT: %switch.load = load float, float* %switch.gep ; CHECK-NEXT: br label %sw.epilog ; CHECK: sw.epilog: ; CHECK-NEXT: %a.0 = phi i8 [ %switch.masked, %switch.lookup ], [ 7, %entry ] ; CHECK-NEXT: %b.0 = phi float [ %switch.load, %switch.lookup ], [ 0x4023FAE140000000, %entry ] ; CHECK-NEXT: call void @dummy(i8 signext %a.0, float %b.0) ; CHECK-NEXT: ret void } ; Switch used to return a string. @.str = private unnamed_addr constant [4 x i8] c"foo\00", align 1 @.str1 = private unnamed_addr constant [4 x i8] c"bar\00", align 1 @.str2 = private unnamed_addr constant [4 x i8] c"baz\00", align 1 @.str3 = private unnamed_addr constant [4 x i8] c"qux\00", align 1 @.str4 = private unnamed_addr constant [6 x i8] c"error\00", align 1 define i8* @foostring(i32 %x) { entry: switch i32 %x, label %sw.default [ i32 0, label %return i32 1, label %sw.bb1 i32 2, label %sw.bb2 i32 3, label %sw.bb3 ] sw.bb1: br label %return sw.bb2: br label %return sw.bb3: br label %return sw.default: br label %return return: %retval.0 = phi i8* [ getelementptr inbounds ([6 x i8], [6 x i8]* @.str4, i64 0, i64 0), %sw.default ], [ getelementptr inbounds ([4 x i8], [4 x i8]* @.str3, i64 0, i64 0), %sw.bb3 ], [ getelementptr inbounds ([4 x i8], [4 x i8]* @.str2, i64 0, i64 0), %sw.bb2 ], [ getelementptr inbounds ([4 x i8], [4 x i8]* @.str1, i64 0, i64 0), %sw.bb1 ], [ getelementptr inbounds ([4 x i8], [4 x i8]* @.str, i64 0, i64 0), %entry ] ret i8* %retval.0 ; CHECK-LABEL: @foostring( ; CHECK: entry: ; CHECK-NEXT: %switch.tableidx = sub i32 %x, 0 ; CHECK-NEXT: %0 = icmp ult i32 %switch.tableidx, 4 ; CHECK-NEXT: br i1 %0, label %switch.lookup, label %return ; CHECK: switch.lookup: ; CHECK-NEXT: %switch.gep = getelementptr inbounds [4 x i8*], [4 x i8*]* @switch.table.2, i32 0, i32 %switch.tableidx ; CHECK-NEXT: %switch.load = load i8*, i8** %switch.gep ; CHECK-NEXT: ret i8* %switch.load } ; Switch used to initialize two values. The first value is returned, the second ; value is not used. This used to make the transformation generate illegal code. define i32 @earlyreturncrash(i32 %x) { entry: switch i32 %x, label %sw.default [ i32 0, label %sw.epilog i32 1, label %sw.bb1 i32 2, label %sw.bb2 i32 3, label %sw.bb3 ] sw.bb1: br label %sw.epilog sw.bb2: br label %sw.epilog sw.bb3: br label %sw.epilog sw.default: br label %sw.epilog sw.epilog: %a.0 = phi i32 [ 7, %sw.default ], [ 5, %sw.bb3 ], [ 88, %sw.bb2 ], [ 9, %sw.bb1 ], [ 42, %entry ] %b.0 = phi i32 [ 10, %sw.default ], [ 5, %sw.bb3 ], [ 1, %sw.bb2 ], [ 4, %sw.bb1 ], [ 3, %entry ] ret i32 %a.0 ; CHECK-LABEL: @earlyreturncrash( ; CHECK: switch.lookup: ; CHECK-NEXT: %switch.gep = getelementptr inbounds [4 x i32], [4 x i32]* @switch.table.3, i32 0, i32 %switch.tableidx ; CHECK-NEXT: %switch.load = load i32, i32* %switch.gep ; CHECK-NEXT: ret i32 %switch.load ; CHECK: sw.epilog: ; CHECK-NEXT: ret i32 7 } ; Example 7 from http://blog.regehr.org/archives/320 ; It is not dense enough for a regular table, but the results ; can be packed into a bitmap. define i32 @crud(i8 zeroext %c) { entry: %cmp = icmp ult i8 %c, 33 br i1 %cmp, label %lor.end, label %switch.early.test switch.early.test: switch i8 %c, label %lor.rhs [ i8 92, label %lor.end i8 62, label %lor.end i8 60, label %lor.end i8 59, label %lor.end i8 58, label %lor.end i8 46, label %lor.end i8 44, label %lor.end i8 34, label %lor.end i8 39, label %switch.edge ] switch.edge: br label %lor.end lor.rhs: br label %lor.end lor.end: %0 = phi i1 [ true, %switch.early.test ], [ false, %lor.rhs ], [ true, %entry ], [ true, %switch.early.test ], [ true, %switch.early.test ], [ true, %switch.early.test ], [ true, %switch.early.test ], [ true, %switch.early.test ], [ true, %switch.early.test ], [ true, %switch.early.test ], [ true, %switch.edge ] %lor.ext = zext i1 %0 to i32 ret i32 %lor.ext ; CHECK-LABEL: @crud( ; CHECK: entry: ; CHECK-NEXT: %cmp = icmp ult i8 %c, 33 ; CHECK-NEXT: br i1 %cmp, label %lor.end, label %switch.early.test ; CHECK: switch.early.test: ; CHECK-NEXT: %switch.tableidx = sub i8 %c, 34 ; CHECK-NEXT: %0 = icmp ult i8 %switch.tableidx, 59 ; CHECK-NEXT: br i1 %0, label %switch.lookup, label %lor.end ; CHECK: switch.lookup: ; CHECK-NEXT: %switch.cast = zext i8 %switch.tableidx to i59 ; CHECK-NEXT: %switch.shiftamt = mul i59 %switch.cast, 1 ; CHECK-NEXT: %switch.downshift = lshr i59 -288230375765830623, %switch.shiftamt ; CHECK-NEXT: %switch.masked = trunc i59 %switch.downshift to i1 ; CHECK-NEXT: br label %lor.end ; CHECK: lor.end: ; CHECK-NEXT: %1 = phi i1 [ true, %entry ], [ %switch.masked, %switch.lookup ], [ false, %switch.early.test ] ; CHECK-NEXT: %lor.ext = zext i1 %1 to i32 ; CHECK-NEXT: ret i32 %lor.ext } ; PR13946 define i32 @overflow(i32 %type) { entry: switch i32 %type, label %sw.default [ i32 -2147483648, label %sw.bb i32 0, label %sw.bb i32 1, label %sw.bb1 i32 2, label %sw.bb2 i32 -2147483645, label %sw.bb3 i32 3, label %sw.bb3 ] sw.bb: br label %if.end sw.bb1: br label %if.end sw.bb2: br label %if.end sw.bb3: br label %if.end sw.default: br label %if.end if.else: br label %if.end if.end: %dirent_type.0 = phi i32 [ 3, %sw.default ], [ 6, %sw.bb3 ], [ 5, %sw.bb2 ], [ 0, %sw.bb1 ], [ 3, %sw.bb ], [ 0, %if.else ] ret i32 %dirent_type.0 ; CHECK-LABEL: define i32 @overflow( ; CHECK: switch ; CHECK: phi } ; PR13985 define i1 @undef(i32 %tmp) { bb: switch i32 %tmp, label %bb3 [ i32 0, label %bb1 i32 1, label %bb1 i32 7, label %bb2 i32 8, label %bb2 ] bb1: br label %bb3 bb2: br label %bb3 bb3: %tmp4 = phi i1 [ undef, %bb ], [ false, %bb2 ], [ true, %bb1 ] ret i1 %tmp4 ; CHECK-LABEL: define i1 @undef( ; CHECK: %switch.cast = trunc i32 %switch.tableidx to i9 ; CHECK: %switch.downshift = lshr i9 3, %switch.shiftamt } ; Also handle large switches that would be rejected by ; isValueEqualityComparison() ; CHECK: large ; CHECK-NOT: switch i32 define i32 @large(i32 %x) { entry: %cmp = icmp slt i32 %x, 0 br i1 %cmp, label %if.then, label %if.end if.then: %mul = mul i32 %x, -10 br label %if.end if.end: %x.addr.0 = phi i32 [ %mul, %if.then ], [ %x, %entry ] switch i32 %x.addr.0, label %return [ i32 199, label %sw.bb203 i32 1, label %sw.bb1 i32 2, label %sw.bb2 i32 3, label %sw.bb3 i32 4, label %sw.bb4 i32 5, label %sw.bb5 i32 6, label %sw.bb6 i32 7, label %sw.bb7 i32 8, label %sw.bb8 i32 9, label %sw.bb9 i32 10, label %sw.bb10 i32 11, label %sw.bb11 i32 12, label %sw.bb12 i32 13, label %sw.bb13 i32 14, label %sw.bb14 i32 15, label %sw.bb15 i32 16, label %sw.bb16 i32 17, label %sw.bb17 i32 18, label %sw.bb18 i32 19, label %sw.bb19 i32 20, label %sw.bb20 i32 21, label %sw.bb21 i32 22, label %sw.bb22 i32 23, label %sw.bb23 i32 24, label %sw.bb24 i32 25, label %sw.bb25 i32 26, label %sw.bb26 i32 27, label %sw.bb27 i32 28, label %sw.bb28 i32 29, label %sw.bb29 i32 30, label %sw.bb30 i32 31, label %sw.bb31 i32 32, label %sw.bb32 i32 33, label %sw.bb33 i32 34, label %sw.bb34 i32 35, label %sw.bb35 i32 36, label %sw.bb37 i32 37, label %sw.bb38 i32 38, label %sw.bb39 i32 39, label %sw.bb40 i32 40, label %sw.bb41 i32 41, label %sw.bb42 i32 42, label %sw.bb43 i32 43, label %sw.bb44 i32 44, label %sw.bb45 i32 45, label %sw.bb47 i32 46, label %sw.bb48 i32 47, label %sw.bb49 i32 48, label %sw.bb50 i32 49, label %sw.bb51 i32 50, label %sw.bb52 i32 51, label %sw.bb53 i32 52, label %sw.bb54 i32 53, label %sw.bb55 i32 54, label %sw.bb56 i32 55, label %sw.bb58 i32 56, label %sw.bb59 i32 57, label %sw.bb60 i32 58, label %sw.bb61 i32 59, label %sw.bb62 i32 60, label %sw.bb63 i32 61, label %sw.bb64 i32 62, label %sw.bb65 i32 63, label %sw.bb66 i32 64, label %sw.bb67 i32 65, label %sw.bb68 i32 66, label %sw.bb69 i32 67, label %sw.bb70 i32 68, label %sw.bb71 i32 69, label %sw.bb72 i32 70, label %sw.bb73 i32 71, label %sw.bb74 i32 72, label %sw.bb76 i32 73, label %sw.bb77 i32 74, label %sw.bb78 i32 75, label %sw.bb79 i32 76, label %sw.bb80 i32 77, label %sw.bb81 i32 78, label %sw.bb82 i32 79, label %sw.bb83 i32 80, label %sw.bb84 i32 81, label %sw.bb85 i32 82, label %sw.bb86 i32 83, label %sw.bb87 i32 84, label %sw.bb88 i32 85, label %sw.bb89 i32 86, label %sw.bb90 i32 87, label %sw.bb91 i32 88, label %sw.bb92 i32 89, label %sw.bb93 i32 90, label %sw.bb94 i32 91, label %sw.bb95 i32 92, label %sw.bb96 i32 93, label %sw.bb97 i32 94, label %sw.bb98 i32 95, label %sw.bb99 i32 96, label %sw.bb100 i32 97, label %sw.bb101 i32 98, label %sw.bb102 i32 99, label %sw.bb103 i32 100, label %sw.bb104 i32 101, label %sw.bb105 i32 102, label %sw.bb106 i32 103, label %sw.bb107 i32 104, label %sw.bb108 i32 105, label %sw.bb109 i32 106, label %sw.bb110 i32 107, label %sw.bb111 i32 108, label %sw.bb112 i32 109, label %sw.bb113 i32 110, label %sw.bb114 i32 111, label %sw.bb115 i32 112, label %sw.bb116 i32 113, label %sw.bb117 i32 114, label %sw.bb118 i32 115, label %sw.bb119 i32 116, label %sw.bb120 i32 117, label %sw.bb121 i32 118, label %sw.bb122 i32 119, label %sw.bb123 i32 120, label %sw.bb124 i32 121, label %sw.bb125 i32 122, label %sw.bb126 i32 123, label %sw.bb127 i32 124, label %sw.bb128 i32 125, label %sw.bb129 i32 126, label %sw.bb130 i32 127, label %sw.bb131 i32 128, label %sw.bb132 i32 129, label %sw.bb133 i32 130, label %sw.bb134 i32 131, label %sw.bb135 i32 132, label %sw.bb136 i32 133, label %sw.bb137 i32 134, label %sw.bb138 i32 135, label %sw.bb139 i32 136, label %sw.bb140 i32 137, label %sw.bb141 i32 138, label %sw.bb142 i32 139, label %sw.bb143 i32 140, label %sw.bb144 i32 141, label %sw.bb145 i32 142, label %sw.bb146 i32 143, label %sw.bb147 i32 144, label %sw.bb148 i32 145, label %sw.bb149 i32 146, label %sw.bb150 i32 147, label %sw.bb151 i32 148, label %sw.bb152 i32 149, label %sw.bb153 i32 150, label %sw.bb154 i32 151, label %sw.bb155 i32 152, label %sw.bb156 i32 153, label %sw.bb157 i32 154, label %sw.bb158 i32 155, label %sw.bb159 i32 156, label %sw.bb160 i32 157, label %sw.bb161 i32 158, label %sw.bb162 i32 159, label %sw.bb163 i32 160, label %sw.bb164 i32 161, label %sw.bb165 i32 162, label %sw.bb166 i32 163, label %sw.bb167 i32 164, label %sw.bb168 i32 165, label %sw.bb169 i32 166, label %sw.bb170 i32 167, label %sw.bb171 i32 168, label %sw.bb172 i32 169, label %sw.bb173 i32 170, label %sw.bb174 i32 171, label %sw.bb175 i32 172, label %sw.bb176 i32 173, label %sw.bb177 i32 174, label %sw.bb178 i32 175, label %sw.bb179 i32 176, label %sw.bb180 i32 177, label %sw.bb181 i32 178, label %sw.bb182 i32 179, label %sw.bb183 i32 180, label %sw.bb184 i32 181, label %sw.bb185 i32 182, label %sw.bb186 i32 183, label %sw.bb187 i32 184, label %sw.bb188 i32 185, label %sw.bb189 i32 186, label %sw.bb190 i32 187, label %sw.bb191 i32 188, label %sw.bb192 i32 189, label %sw.bb193 i32 190, label %sw.bb194 i32 191, label %sw.bb195 i32 192, label %sw.bb196 i32 193, label %sw.bb197 i32 194, label %sw.bb198 i32 195, label %sw.bb199 i32 196, label %sw.bb200 i32 197, label %sw.bb201 i32 198, label %sw.bb202 ] sw.bb1: br label %return sw.bb2: br label %return sw.bb3: br label %return sw.bb4: br label %return sw.bb5: br label %return sw.bb6: br label %return sw.bb7: br label %return sw.bb8: br label %return sw.bb9: br label %return sw.bb10: br label %return sw.bb11: br label %return sw.bb12: br label %return sw.bb13: br label %return sw.bb14: br label %return sw.bb15: br label %return sw.bb16: br label %return sw.bb17: br label %return sw.bb18: br label %return sw.bb19: br label %return sw.bb20: br label %return sw.bb21: br label %return sw.bb22: br label %return sw.bb23: br label %return sw.bb24: br label %return sw.bb25: br label %return sw.bb26: br label %return sw.bb27: br label %return sw.bb28: br label %return sw.bb29: br label %return sw.bb30: br label %return sw.bb31: br label %return sw.bb32: br label %return sw.bb33: br label %return sw.bb34: br label %return sw.bb35: br label %return sw.bb37: br label %return sw.bb38: br label %return sw.bb39: br label %return sw.bb40: br label %return sw.bb41: br label %return sw.bb42: br label %return sw.bb43: br label %return sw.bb44: br label %return sw.bb45: br label %return sw.bb47: br label %return sw.bb48: br label %return sw.bb49: br label %return sw.bb50: br label %return sw.bb51: br label %return sw.bb52: br label %return sw.bb53: br label %return sw.bb54: br label %return sw.bb55: br label %return sw.bb56: br label %return sw.bb58: br label %return sw.bb59: br label %return sw.bb60: br label %return sw.bb61: br label %return sw.bb62: br label %return sw.bb63: br label %return sw.bb64: br label %return sw.bb65: br label %return sw.bb66: br label %return sw.bb67: br label %return sw.bb68: br label %return sw.bb69: br label %return sw.bb70: br label %return sw.bb71: br label %return sw.bb72: br label %return sw.bb73: br label %return sw.bb74: br label %return sw.bb76: br label %return sw.bb77: br label %return sw.bb78: br label %return sw.bb79: br label %return sw.bb80: br label %return sw.bb81: br label %return sw.bb82: br label %return sw.bb83: br label %return sw.bb84: br label %return sw.bb85: br label %return sw.bb86: br label %return sw.bb87: br label %return sw.bb88: br label %return sw.bb89: br label %return sw.bb90: br label %return sw.bb91: br label %return sw.bb92: br label %return sw.bb93: br label %return sw.bb94: br label %return sw.bb95: br label %return sw.bb96: br label %return sw.bb97: br label %return sw.bb98: br label %return sw.bb99: br label %return sw.bb100: br label %return sw.bb101: br label %return sw.bb102: br label %return sw.bb103: br label %return sw.bb104: br label %return sw.bb105: br label %return sw.bb106: br label %return sw.bb107: br label %return sw.bb108: br label %return sw.bb109: br label %return sw.bb110: br label %return sw.bb111: br label %return sw.bb112: br label %return sw.bb113: br label %return sw.bb114: br label %return sw.bb115: br label %return sw.bb116: br label %return sw.bb117: br label %return sw.bb118: br label %return sw.bb119: br label %return sw.bb120: br label %return sw.bb121: br label %return sw.bb122: br label %return sw.bb123: br label %return sw.bb124: br label %return sw.bb125: br label %return sw.bb126: br label %return sw.bb127: br label %return sw.bb128: br label %return sw.bb129: br label %return sw.bb130: br label %return sw.bb131: br label %return sw.bb132: br label %return sw.bb133: br label %return sw.bb134: br label %return sw.bb135: br label %return sw.bb136: br label %return sw.bb137: br label %return sw.bb138: br label %return sw.bb139: br label %return sw.bb140: br label %return sw.bb141: br label %return sw.bb142: br label %return sw.bb143: br label %return sw.bb144: br label %return sw.bb145: br label %return sw.bb146: br label %return sw.bb147: br label %return sw.bb148: br label %return sw.bb149: br label %return sw.bb150: br label %return sw.bb151: br label %return sw.bb152: br label %return sw.bb153: br label %return sw.bb154: br label %return sw.bb155: br label %return sw.bb156: br label %return sw.bb157: br label %return sw.bb158: br label %return sw.bb159: br label %return sw.bb160: br label %return sw.bb161: br label %return sw.bb162: br label %return sw.bb163: br label %return sw.bb164: br label %return sw.bb165: br label %return sw.bb166: br label %return sw.bb167: br label %return sw.bb168: br label %return sw.bb169: br label %return sw.bb170: br label %return sw.bb171: br label %return sw.bb172: br label %return sw.bb173: br label %return sw.bb174: br label %return sw.bb175: br label %return sw.bb176: br label %return sw.bb177: br label %return sw.bb178: br label %return sw.bb179: br label %return sw.bb180: br label %return sw.bb181: br label %return sw.bb182: br label %return sw.bb183: br label %return sw.bb184: br label %return sw.bb185: br label %return sw.bb186: br label %return sw.bb187: br label %return sw.bb188: br label %return sw.bb189: br label %return sw.bb190: br label %return sw.bb191: br label %return sw.bb192: br label %return sw.bb193: br label %return sw.bb194: br label %return sw.bb195: br label %return sw.bb196: br label %return sw.bb197: br label %return sw.bb198: br label %return sw.bb199: br label %return sw.bb200: br label %return sw.bb201: br label %return sw.bb202: br label %return sw.bb203: br label %return return: %retval.0 = phi i32 [ 39204, %sw.bb202 ], [ 38809, %sw.bb201 ], [ 38416, %sw.bb200 ], [ 38025, %sw.bb199 ], [ 37636, %sw.bb198 ], [ 37249, %sw.bb197 ], [ 36864, %sw.bb196 ], [ 36481, %sw.bb195 ], [ 36100, %sw.bb194 ], [ 35721, %sw.bb193 ], [ 35344, %sw.bb192 ], [ 34969, %sw.bb191 ], [ 34596, %sw.bb190 ], [ 34225, %sw.bb189 ], [ 33856, %sw.bb188 ], [ 33489, %sw.bb187 ], [ 33124, %sw.bb186 ], [ 32761, %sw.bb185 ], [ 32400, %sw.bb184 ], [ 32041, %sw.bb183 ], [ 31684, %sw.bb182 ], [ 31329, %sw.bb181 ], [ 30976, %sw.bb180 ], [ 30625, %sw.bb179 ], [ 30276, %sw.bb178 ], [ 29929, %sw.bb177 ], [ 29584, %sw.bb176 ], [ 29241, %sw.bb175 ], [ 28900, %sw.bb174 ], [ 28561, %sw.bb173 ], [ 28224, %sw.bb172 ], [ 27889, %sw.bb171 ], [ 27556, %sw.bb170 ], [ 27225, %sw.bb169 ], [ 26896, %sw.bb168 ], [ 26569, %sw.bb167 ], [ 26244, %sw.bb166 ], [ 25921, %sw.bb165 ], [ 25600, %sw.bb164 ], [ 25281, %sw.bb163 ], [ 24964, %sw.bb162 ], [ 24649, %sw.bb161 ], [ 24336, %sw.bb160 ], [ 24025, %sw.bb159 ], [ 23716, %sw.bb158 ], [ 23409, %sw.bb157 ], [ 23104, %sw.bb156 ], [ 22801, %sw.bb155 ], [ 22500, %sw.bb154 ], [ 22201, %sw.bb153 ], [ 21904, %sw.bb152 ], [ 21609, %sw.bb151 ], [ 21316, %sw.bb150 ], [ 21025, %sw.bb149 ], [ 20736, %sw.bb148 ], [ 20449, %sw.bb147 ], [ 20164, %sw.bb146 ], [ 19881, %sw.bb145 ], [ 19600, %sw.bb144 ], [ 19321, %sw.bb143 ], [ 19044, %sw.bb142 ], [ 18769, %sw.bb141 ], [ 18496, %sw.bb140 ], [ 18225, %sw.bb139 ], [ 17956, %sw.bb138 ], [ 17689, %sw.bb137 ], [ 17424, %sw.bb136 ], [ 17161, %sw.bb135 ], [ 16900, %sw.bb134 ], [ 16641, %sw.bb133 ], [ 16384, %sw.bb132 ], [ 16129, %sw.bb131 ], [ 15876, %sw.bb130 ], [ 15625, %sw.bb129 ], [ 15376, %sw.bb128 ], [ 15129, %sw.bb127 ], [ 14884, %sw.bb126 ], [ 14641, %sw.bb125 ], [ 14400, %sw.bb124 ], [ 14161, %sw.bb123 ], [ 13924, %sw.bb122 ], [ 13689, %sw.bb121 ], [ 13456, %sw.bb120 ], [ 13225, %sw.bb119 ], [ 12996, %sw.bb118 ], [ 12769, %sw.bb117 ], [ 12544, %sw.bb116 ], [ 12321, %sw.bb115 ], [ 12100, %sw.bb114 ], [ 11881, %sw.bb113 ], [ 11664, %sw.bb112 ], [ 11449, %sw.bb111 ], [ 11236, %sw.bb110 ], [ 11025, %sw.bb109 ], [ 10816, %sw.bb108 ], [ 10609, %sw.bb107 ], [ 10404, %sw.bb106 ], [ 10201, %sw.bb105 ], [ 10000, %sw.bb104 ], [ 9801, %sw.bb103 ], [ 9604, %sw.bb102 ], [ 9409, %sw.bb101 ], [ 9216, %sw.bb100 ], [ 9025, %sw.bb99 ], [ 8836, %sw.bb98 ], [ 8649, %sw.bb97 ], [ 8464, %sw.bb96 ], [ 8281, %sw.bb95 ], [ 8100, %sw.bb94 ], [ 7921, %sw.bb93 ], [ 7744, %sw.bb92 ], [ 7569, %sw.bb91 ], [ 7396, %sw.bb90 ], [ 7225, %sw.bb89 ], [ 7056, %sw.bb88 ], [ 6889, %sw.bb87 ], [ 6724, %sw.bb86 ], [ 6561, %sw.bb85 ], [ 6400, %sw.bb84 ], [ 6241, %sw.bb83 ], [ 6084, %sw.bb82 ], [ 5929, %sw.bb81 ], [ 5776, %sw.bb80 ], [ 5625, %sw.bb79 ], [ 5476, %sw.bb78 ], [ 5329, %sw.bb77 ], [ 5184, %sw.bb76 ], [ 5112, %sw.bb74 ], [ 4900, %sw.bb73 ], [ 4761, %sw.bb72 ], [ 4624, %sw.bb71 ], [ 4489, %sw.bb70 ], [ 4356, %sw.bb69 ], [ 4225, %sw.bb68 ], [ 4096, %sw.bb67 ], [ 3969, %sw.bb66 ], [ 3844, %sw.bb65 ], [ 3721, %sw.bb64 ], [ 3600, %sw.bb63 ], [ 3481, %sw.bb62 ], [ 3364, %sw.bb61 ], [ 3249, %sw.bb60 ], [ 3136, %sw.bb59 ], [ 3025, %sw.bb58 ], [ 2970, %sw.bb56 ], [ 2809, %sw.bb55 ], [ 2704, %sw.bb54 ], [ 2601, %sw.bb53 ], [ 2500, %sw.bb52 ], [ 2401, %sw.bb51 ], [ 2304, %sw.bb50 ], [ 2209, %sw.bb49 ], [ 2116, %sw.bb48 ], [ 2025, %sw.bb47 ], [ 1980, %sw.bb45 ], [ 1849, %sw.bb44 ], [ 1764, %sw.bb43 ], [ 1681, %sw.bb42 ], [ 1600, %sw.bb41 ], [ 1521, %sw.bb40 ], [ 1444, %sw.bb39 ], [ 1369, %sw.bb38 ], [ 1296, %sw.bb37 ], [ 1260, %sw.bb35 ], [ 1156, %sw.bb34 ], [ 1089, %sw.bb33 ], [ 1024, %sw.bb32 ], [ 961, %sw.bb31 ], [ 900, %sw.bb30 ], [ 841, %sw.bb29 ], [ 784, %sw.bb28 ], [ 729, %sw.bb27 ], [ 676, %sw.bb26 ], [ 625, %sw.bb25 ], [ 576, %sw.bb24 ], [ 529, %sw.bb23 ], [ 484, %sw.bb22 ], [ 441, %sw.bb21 ], [ 400, %sw.bb20 ], [ 361, %sw.bb19 ], [ 342, %sw.bb18 ], [ 289, %sw.bb17 ], [ 256, %sw.bb16 ], [ 225, %sw.bb15 ], [ 196, %sw.bb14 ], [ 169, %sw.bb13 ], [ 144, %sw.bb12 ], [ 121, %sw.bb11 ], [ 100, %sw.bb10 ], [ 81, %sw.bb9 ], [ 64, %sw.bb8 ], [ 49, %sw.bb7 ], [ 36, %sw.bb6 ], [ 25, %sw.bb5 ], [ 16, %sw.bb4 ], [ 9, %sw.bb3 ], [ 4, %sw.bb2 ], [ 1, %sw.bb1 ], [ 39601, %sw.bb203 ], [ 0, %if.end ] ret i32 %retval.0 } define i32 @cprop(i32 %x, i32 %y) { entry: switch i32 %x, label %sw.default [ i32 1, label %return i32 2, label %sw.bb1 i32 3, label %sw.bb2 i32 4, label %sw.bb2 i32 5, label %sw.bb2 i32 6, label %sw.bb3 i32 7, label %sw.bb3 ] sw.bb1: br label %return sw.bb2: %and = and i32 %x, 1 %and.ptr = inttoptr i32 %and to i8* %tobool = icmp ne i8* %and.ptr, null %cond = select i1 %tobool, i32 -123, i32 456 %sub = sub nsw i32 %x, %cond br label %return sw.bb3: %trunc = trunc i32 %x to i8 %sext = sext i8 %trunc to i32 %select.i = icmp sgt i32 %sext, 0 %select = select i1 %select.i, i32 %sext, i32 %y br label %return sw.default: br label %return return: %retval.0 = phi i32 [ 123, %sw.default ], [ %select, %sw.bb3 ], [ %sub, %sw.bb2 ], [ 42, %sw.bb1 ], [ 5, %entry ] ret i32 %retval.0 ; CHECK-LABEL: @cprop( ; CHECK: switch.lookup: ; CHECK: %switch.gep = getelementptr inbounds [7 x i32], [7 x i32]* @switch.table.5, i32 0, i32 %switch.tableidx } define i32 @unreachable_case(i32 %x) { entry: switch i32 %x, label %sw.default [ i32 0, label %sw.bb i32 1, label %sw.bb i32 2, label %sw.bb i32 3, label %sw.bb1 i32 4, label %sw.bb2 i32 5, label %sw.bb3 i32 6, label %sw.bb3 i32 7, label %sw.bb3 i32 8, label %sw.bb3 ] sw.bb: br label %return sw.bb1: unreachable sw.bb2: br label %return sw.bb3: br label %return sw.default: br label %return return: %retval.0 = phi i32 [ 1, %sw.bb3 ], [ -1, %sw.bb2 ], [ 0, %sw.bb ], [ 2, %sw.default ] ret i32 %retval.0 ; CHECK-LABEL: @unreachable_case( ; CHECK: switch.lookup: ; CHECK: getelementptr inbounds [9 x i32], [9 x i32]* @switch.table.6, i32 0, i32 %switch.tableidx } define i32 @unreachable_default(i32 %x) { entry: switch i32 %x, label %default [ i32 0, label %bb0 i32 1, label %bb1 i32 2, label %bb2 i32 3, label %bb3 ] bb0: br label %return bb1: br label %return bb2: br label %return bb3: br label %return default: unreachable return: %retval = phi i32 [ 42, %bb0 ], [ 52, %bb1 ], [ 1, %bb2 ], [ 2, %bb3 ] ret i32 %retval ; CHECK-LABEL: @unreachable_default( ; CHECK: entry: ; CHECK-NEXT: %switch.tableidx = sub i32 %x, 0 ; CHECK-NOT: icmp ; CHECK-NOT: br 1i ; CHECK-NEXT: %switch.gep = getelementptr inbounds [4 x i32], [4 x i32]* @switch.table.7, i32 0, i32 %switch.tableidx ; CHECK-NEXT: %switch.load = load i32, i32* %switch.gep ; CHECK-NEXT: ret i32 %switch.load } ; Don't create a table with illegal type define i96 @illegaltype(i32 %c) { entry: switch i32 %c, label %sw.default [ i32 42, label %return i32 43, label %sw.bb1 i32 44, label %sw.bb2 i32 45, label %sw.bb3 i32 46, label %sw.bb4 ] sw.bb1: br label %return sw.bb2: br label %return sw.bb3: br label %return sw.bb4: br label %return sw.default: br label %return return: %retval.0 = phi i96 [ 15, %sw.default ], [ 27, %sw.bb4 ], [ -1, %sw.bb3 ], [ 0, %sw.bb2 ], [ 123, %sw.bb1 ], [ 55, %entry ] ret i96 %retval.0 ; CHECK-LABEL: @illegaltype( ; CHECK-NOT: @switch.table ; CHECK: switch i32 %c } ; If we can build a lookup table without any holes, we don't need a default result. declare void @exit(i32) define i32 @nodefaultnoholes(i32 %c) { entry: switch i32 %c, label %sw.default [ i32 0, label %return i32 1, label %sw.bb1 i32 2, label %sw.bb2 i32 3, label %sw.bb3 ] sw.bb1: br label %return sw.bb2: br label %return sw.bb3: br label %return sw.default: call void @exit(i32 1) unreachable return: %x = phi i32 [ -1, %sw.bb3 ], [ 0, %sw.bb2 ], [ 123, %sw.bb1 ], [ 55, %entry ] ret i32 %x ; CHECK-LABEL: @nodefaultnoholes( ; CHECK: @switch.table ; CHECK-NOT: switch i32 } ; This lookup table will have holes, so we need to test for the holes. define i32 @nodefaultwithholes(i32 %c) { entry: switch i32 %c, label %sw.default [ i32 0, label %return i32 1, label %sw.bb1 i32 2, label %sw.bb2 i32 3, label %sw.bb3 i32 5, label %sw.bb3 ] sw.bb1: br label %return sw.bb2: br label %return sw.bb3: br label %return sw.default: call void @exit(i32 1) unreachable return: %x = phi i32 [ -1, %sw.bb3 ], [ 0, %sw.bb2 ], [ 123, %sw.bb1 ], [ 55, %entry ] ret i32 %x ; CHECK-LABEL: @nodefaultwithholes( ; CHECK: entry: ; CHECK: br i1 %{{.*}}, label %switch.hole_check, label %sw.default ; CHECK: switch.hole_check: ; CHECK-NEXT: %switch.maskindex = trunc i32 %switch.tableidx to i8 ; CHECK-NEXT: %switch.shifted = lshr i8 47, %switch.maskindex ; The mask is binary 101111. ; CHECK-NEXT: %switch.lobit = trunc i8 %switch.shifted to i1 ; CHECK-NEXT: br i1 %switch.lobit, label %switch.lookup, label %sw.default ; CHECK-NOT: switch i32 } ; We don't build lookup tables with holes for switches with less than four cases. define i32 @threecasesholes(i32 %c) { entry: switch i32 %c, label %sw.default [ i32 0, label %return i32 1, label %sw.bb1 i32 3, label %sw.bb2 ] sw.bb1: br label %return sw.bb2: br label %return sw.default: br label %return return: %x = phi i32 [ %c, %sw.default ], [ 5, %sw.bb2 ], [ 7, %sw.bb1 ], [ 9, %entry ] ret i32 %x ; CHECK-LABEL: @threecasesholes( ; CHECK: switch i32 ; CHECK-NOT: @switch.table } ; We build lookup tables for switches with three or more cases. define i32 @threecases(i32 %c) { entry: switch i32 %c, label %sw.default [ i32 0, label %return i32 1, label %sw.bb1 i32 2, label %sw.bb2 ] sw.bb1: br label %return sw.bb2: br label %return sw.default: br label %return return: %x = phi i32 [ 3, %sw.default ], [ 5, %sw.bb2 ], [ 7, %sw.bb1 ], [ 10, %entry ] ret i32 %x ; CHECK-LABEL: @threecases( ; CHECK-NOT: switch i32 ; CHECK: @switch.table } ; We don't build tables for switches with two cases. define i32 @twocases(i32 %c) { entry: switch i32 %c, label %sw.default [ i32 0, label %return i32 1, label %sw.bb1 ] sw.bb1: br label %return sw.default: br label %return return: %x = phi i32 [ 3, %sw.default ], [ 7, %sw.bb1 ], [ 9, %entry ] ret i32 %x ; CHECK-LABEL: @twocases( ; CHECK-NOT: switch i32 ; CHECK-NOT: @switch.table ; CHECK: %switch.selectcmp ; CHECK-NEXT: %switch.select ; CHECK-NEXT: %switch.selectcmp1 ; CHECK-NEXT: %switch.select2 } ; Don't build tables for switches with TLS variables. @tls_a = thread_local global i32 0 @tls_b = thread_local global i32 0 @tls_c = thread_local global i32 0 @tls_d = thread_local global i32 0 define i32* @tls(i32 %x) { entry: switch i32 %x, label %sw.default [ i32 0, label %return i32 1, label %sw.bb1 i32 2, label %sw.bb2 ] sw.bb1: br label %return sw.bb2: br label %return sw.default: br label %return return: %retval.0 = phi i32* [ @tls_d, %sw.default ], [ @tls_c, %sw.bb2 ], [ @tls_b, %sw.bb1 ], [ @tls_a, %entry ] ret i32* %retval.0 ; CHECK-LABEL: @tls( ; CHECK: switch i32 ; CHECK-NOT: @switch.table } ; Don't build tables for switches with dllimport variables. @dllimport_a = external dllimport global [3x i32] @dllimport_b = external dllimport global [3x i32] @dllimport_c = external dllimport global [3x i32] @dllimport_d = external dllimport global [3x i32] define i32* @dllimport(i32 %x) { entry: switch i32 %x, label %sw.default [ i32 0, label %return i32 1, label %sw.bb1 i32 2, label %sw.bb2 ] sw.bb1: br label %return sw.bb2: br label %return sw.default: br label %return return: %retval.0 = phi i32* [ getelementptr inbounds ([3 x i32], [3 x i32]* @dllimport_d, i32 0, i32 0), %sw.default ], [ getelementptr inbounds ([3 x i32], [3 x i32]* @dllimport_c, i32 0, i32 0), %sw.bb2 ], [ getelementptr inbounds ([3 x i32], [3 x i32]* @dllimport_b, i32 0, i32 0), %sw.bb1 ], [ getelementptr inbounds ([3 x i32], [3 x i32]* @dllimport_a, i32 0, i32 0), %entry ] ret i32* %retval.0 ; CHECK-LABEL: @dllimport( ; CHECK: switch i32 ; CHECK-NOT: @switch.table } ; We can use linear mapping. define i8 @linearmap1(i32 %c) { entry: switch i32 %c, label %sw.default [ i32 10, label %return i32 11, label %sw.bb1 i32 12, label %sw.bb2 i32 13, label %sw.bb3 ] sw.bb1: br label %return sw.bb2: br label %return sw.bb3: br label %return sw.default: br label %return return: %x = phi i8 [ 3, %sw.default ], [ 3, %sw.bb3 ], [ 8, %sw.bb2 ], [ 13, %sw.bb1 ], [ 18, %entry ] ret i8 %x ; CHECK-LABEL: @linearmap1( ; CHECK: entry: ; CHECK-NEXT: %switch.tableidx = sub i32 %c, 10 ; CHECK: switch.lookup: ; CHECK-NEXT: %switch.idx.cast = trunc i32 %switch.tableidx to i8 ; CHECK-NEXT: %switch.idx.mult = mul i8 %switch.idx.cast, -5 ; CHECK-NEXT: %switch.offset = add i8 %switch.idx.mult, 18 ; CHECK-NEXT: ret i8 %switch.offset } ; Linear mapping in a different configuration. define i32 @linearmap2(i8 %c) { entry: switch i8 %c, label %sw.default [ i8 -10, label %return i8 -11, label %sw.bb1 i8 -12, label %sw.bb2 i8 -13, label %sw.bb3 ] sw.bb1: br label %return sw.bb2: br label %return sw.bb3: br label %return sw.default: br label %return return: %x = phi i32 [ 3, %sw.default ], [ 18, %sw.bb3 ], [ 19, %sw.bb2 ], [ 20, %sw.bb1 ], [ 21, %entry ] ret i32 %x ; CHECK-LABEL: @linearmap2( ; CHECK: entry: ; CHECK-NEXT: %switch.tableidx = sub i8 %c, -13 ; CHECK: switch.lookup: ; CHECK-NEXT: %switch.idx.cast = zext i8 %switch.tableidx to i32 ; CHECK-NEXT: %switch.offset = add i32 %switch.idx.cast, 18 ; CHECK-NEXT: ret i32 %switch.offset } ; Linear mapping with overflows. define i8 @linearmap3(i32 %c) { entry: switch i32 %c, label %sw.default [ i32 10, label %return i32 11, label %sw.bb1 i32 12, label %sw.bb2 i32 13, label %sw.bb3 ] sw.bb1: br label %return sw.bb2: br label %return sw.bb3: br label %return sw.default: br label %return return: %x = phi i8 [ 3, %sw.default ], [ 44, %sw.bb3 ], [ -56, %sw.bb2 ], [ 100, %sw.bb1 ], [ 0, %entry ] ret i8 %x ; CHECK-LABEL: @linearmap3( ; CHECK: entry: ; CHECK-NEXT: %switch.tableidx = sub i32 %c, 10 ; CHECK: switch.lookup: ; CHECK-NEXT: %switch.idx.cast = trunc i32 %switch.tableidx to i8 ; CHECK-NEXT: %switch.idx.mult = mul i8 %switch.idx.cast, 100 ; CHECK-NEXT: ret i8 %switch.idx.mult } ; Linear mapping with with multiplier 1 and offset 0. define i8 @linearmap4(i32 %c) { entry: switch i32 %c, label %sw.default [ i32 -2, label %return i32 -1, label %sw.bb1 i32 0, label %sw.bb2 i32 1, label %sw.bb3 ] sw.bb1: br label %return sw.bb2: br label %return sw.bb3: br label %return sw.default: br label %return return: %x = phi i8 [ 3, %sw.default ], [ 3, %sw.bb3 ], [ 2, %sw.bb2 ], [ 1, %sw.bb1 ], [ 0, %entry ] ret i8 %x ; CHECK-LABEL: @linearmap4( ; CHECK: entry: ; CHECK-NEXT: %switch.tableidx = sub i32 %c, -2 ; CHECK: switch.lookup: ; CHECK-NEXT: %switch.idx.cast = trunc i32 %switch.tableidx to i8 ; CHECK-NEXT: ret i8 %switch.idx.cast } ; Reuse the inverted table range compare. define i32 @reuse_cmp1(i32 %x) { entry: switch i32 %x, label %sw.default [ i32 0, label %sw.bb i32 1, label %sw.bb1 i32 2, label %sw.bb2 i32 3, label %sw.bb3 ] sw.bb: br label %sw.epilog sw.bb1: br label %sw.epilog sw.bb2: br label %sw.epilog sw.bb3: br label %sw.epilog sw.default: br label %sw.epilog sw.epilog: %r.0 = phi i32 [ 0, %sw.default ], [ 13, %sw.bb3 ], [ 12, %sw.bb2 ], [ 11, %sw.bb1 ], [ 10, %sw.bb ] %cmp = icmp eq i32 %r.0, 0 ; This compare can be "replaced". br i1 %cmp, label %if.then, label %if.end if.then: br label %return if.end: br label %return return: %retval.0 = phi i32 [ 100, %if.then ], [ %r.0, %if.end ] ret i32 %retval.0 ; CHECK-LABEL: @reuse_cmp1( ; CHECK: entry: ; CHECK-NEXT: %switch.tableidx = sub i32 %x, 0 ; CHECK-NEXT: [[C:%.+]] = icmp ult i32 %switch.tableidx, 4 ; CHECK-NEXT: %inverted.cmp = xor i1 [[C]], true ; CHECK: [[R:%.+]] = select i1 %inverted.cmp, i32 100, i32 {{.*}} ; CHECK-NEXT: ret i32 [[R]] } ; Reuse the table range compare. define i32 @reuse_cmp2(i32 %x) { entry: switch i32 %x, label %sw.default [ i32 0, label %sw.bb i32 1, label %sw.bb1 i32 2, label %sw.bb2 i32 3, label %sw.bb3 ] sw.bb: br label %sw.epilog sw.bb1: br label %sw.epilog sw.bb2: br label %sw.epilog sw.bb3: br label %sw.epilog sw.default: br label %sw.epilog sw.epilog: %r.0 = phi i32 [ 4, %sw.default ], [ 3, %sw.bb3 ], [ 2, %sw.bb2 ], [ 1, %sw.bb1 ], [ 0, %sw.bb ] %cmp = icmp ne i32 %r.0, 4 ; This compare can be "replaced". br i1 %cmp, label %if.then, label %if.end if.then: br label %return if.end: br label %return return: %retval.0 = phi i32 [ %r.0, %if.then ], [ 100, %if.end ] ret i32 %retval.0 ; CHECK-LABEL: @reuse_cmp2( ; CHECK: entry: ; CHECK-NEXT: %switch.tableidx = sub i32 %x, 0 ; CHECK-NEXT: [[C:%.+]] = icmp ult i32 %switch.tableidx, 4 ; CHECK: [[R:%.+]] = select i1 [[C]], i32 {{.*}}, i32 100 ; CHECK-NEXT: ret i32 [[R]] } ; Cannot reuse the table range compare, because the default value is the same ; as one of the case values. define i32 @no_reuse_cmp(i32 %x) { entry: switch i32 %x, label %sw.default [ i32 0, label %sw.bb i32 1, label %sw.bb1 i32 2, label %sw.bb2 i32 3, label %sw.bb3 ] sw.bb: br label %sw.epilog sw.bb1: br label %sw.epilog sw.bb2: br label %sw.epilog sw.bb3: br label %sw.epilog sw.default: br label %sw.epilog sw.epilog: %r.0 = phi i32 [ 12, %sw.default ], [ 13, %sw.bb3 ], [ 12, %sw.bb2 ], [ 11, %sw.bb1 ], [ 10, %sw.bb ] %cmp = icmp ne i32 %r.0, 0 br i1 %cmp, label %if.then, label %if.end if.then: br label %return if.end: br label %return return: %retval.0 = phi i32 [ %r.0, %if.then ], [ 100, %if.end ] ret i32 %retval.0 ; CHECK-LABEL: @no_reuse_cmp( ; CHECK: [[S:%.+]] = select ; CHECK-NEXT: %cmp = icmp ne i32 [[S]], 0 ; CHECK-NEXT: [[R:%.+]] = select i1 %cmp, i32 [[S]], i32 100 ; CHECK-NEXT: ret i32 [[R]] } ; Cannot reuse the table range compare, because the phi at the switch merge ; point is not dominated by the switch. define i32 @no_reuse_cmp2(i32 %x, i32 %y) { entry: %ec = icmp ne i32 %y, 0 br i1 %ec, label %switch.entry, label %sw.epilog switch.entry: switch i32 %x, label %sw.default [ i32 0, label %sw.bb i32 1, label %sw.bb1 i32 2, label %sw.bb2 i32 3, label %sw.bb3 ] sw.bb: br label %sw.epilog sw.bb1: br label %sw.epilog sw.bb2: br label %sw.epilog sw.bb3: br label %sw.epilog sw.default: br label %sw.epilog sw.epilog: %r.0 = phi i32 [100, %entry], [ 0, %sw.default ], [ 13, %sw.bb3 ], [ 12, %sw.bb2 ], [ 11, %sw.bb1 ], [ 10, %sw.bb ] %cmp = icmp eq i32 %r.0, 0 ; This compare can be "replaced". br i1 %cmp, label %if.then, label %if.end if.then: br label %return if.end: br label %return return: %retval.0 = phi i32 [ 100, %if.then ], [ %r.0, %if.end ] ret i32 %retval.0 ; CHECK-LABEL: @no_reuse_cmp2( ; CHECK: %r.0 = phi ; CHECK-NEXT: %cmp = icmp eq i32 %r.0, 0 ; CHECK-NEXT: [[R:%.+]] = select i1 %cmp ; CHECK-NEXT: ret i32 [[R]] } define void @pr20210(i8 %x, i1 %y) { ; %z has uses outside of its BB or the phi it feeds into, ; so doing a table lookup and jumping directly to while.cond would ; cause %z to cease dominating all its uses. entry: br i1 %y, label %sw, label %intermediate sw: switch i8 %x, label %end [ i8 7, label %intermediate i8 3, label %intermediate i8 2, label %intermediate i8 1, label %intermediate i8 0, label %intermediate ] intermediate: %z = zext i8 %x to i32 br label %while.cond while.cond: %i = phi i32 [ %z, %intermediate ], [ %j, %while.body ] %b = icmp ne i32 %i, 7 br i1 %b, label %while.body, label %while.end while.body: %j = add i32 %i, 1 br label %while.cond while.end: call void @exit(i32 %z) unreachable end: ret void ; CHECK-LABEL: @pr20210 ; CHECK: switch i8 %x } ; Make sure we do not crash due to trying to generate an unguarded ; lookup (since i3 can only hold values in the range of explicit ; values) and simultaneously trying to generate a branch to deal with ; the fact that we have holes in the range. define i32 @covered_switch_with_bit_tests(i3) { entry: switch i3 %0, label %l6 [ i3 -3, label %l5 i3 -4, label %l5 i3 3, label %l1 i3 2, label %l1 ] l1: br label %l2 l2: %x = phi i32 [ 1, %l1 ], [ 2, %l5 ] br label %l6 l5: br label %l2 l6: %r = phi i32 [ %x, %l2 ], [ 0, %entry ] ret i32 %r ; CHECK-LABEL: @covered_switch_with_bit_tests ; CHECK: entry ; CHECK-NEXT: switch } ; Speculation depth must be limited to avoid a zero-cost instruction cycle. ; CHECK-LABEL: @PR26308( ; CHECK: while.body: ; CHECK-NEXT: br label %while.body define i32 @PR26308(i1 %B, i64 %load) { entry: br label %while.body while.body: br label %cleanup cleanup: %cleanup.dest.slot.0 = phi i1 [ false, %while.body ] br i1 %cleanup.dest.slot.0, label %for.cond, label %cleanup4 for.cond: %e.0 = phi i64* [ undef, %cleanup ], [ %incdec.ptr, %for.cond2 ] %pi = ptrtoint i64* %e.0 to i64 %incdec.ptr = getelementptr inbounds i64, i64* %e.0, i64 1 br label %for.cond2 for.cond2: %storemerge = phi i64 [ %pi, %for.cond ], [ %load, %for.cond2 ] br i1 %B, label %for.cond2, label %for.cond cleanup4: br label %while.body }