1 ; RUN: opt < %s -gvn -S | FileCheck %s 2 3 %struct.A = type { i32 (...)** } 4 @_ZTV1A = available_externally unnamed_addr constant [4 x i8*] [i8* null, i8* bitcast (i8** @_ZTI1A to i8*), i8* bitcast (i32 (%struct.A*)* @_ZN1A3fooEv to i8*), i8* bitcast (i32 (%struct.A*)* @_ZN1A3barEv to i8*)], align 8 5 @_ZTI1A = external constant i8* 6 7 ; Checks if indirect calls can be replaced with direct 8 ; assuming that %vtable == @_ZTV1A (with alignment). 9 ; Checking const propagation across other BBs 10 ; CHECK-LABEL: define void @_Z1gb( 11 12 define void @_Z1gb(i1 zeroext %p) { 13 entry: 14 %call = tail call noalias i8* @_Znwm(i64 8) #4 15 %0 = bitcast i8* %call to %struct.A* 16 tail call void @_ZN1AC1Ev(%struct.A* %0) #1 17 %1 = bitcast i8* %call to i8*** 18 %vtable = load i8**, i8*** %1, align 8 19 %cmp.vtables = icmp eq i8** %vtable, getelementptr inbounds ([4 x i8*], [4 x i8*]* @_ZTV1A, i64 0, i64 2) 20 tail call void @llvm.assume(i1 %cmp.vtables) 21 br i1 %p, label %if.then, label %if.else 22 23 if.then: ; preds = %entry 24 %vtable1.cast = bitcast i8** %vtable to i32 (%struct.A*)** 25 %2 = load i32 (%struct.A*)*, i32 (%struct.A*)** %vtable1.cast, align 8 26 27 ; CHECK: call i32 @_ZN1A3fooEv( 28 %call2 = tail call i32 %2(%struct.A* %0) #1 29 30 br label %if.end 31 32 if.else: ; preds = %entry 33 %vfn47 = getelementptr inbounds i8*, i8** %vtable, i64 1 34 %vfn4 = bitcast i8** %vfn47 to i32 (%struct.A*)** 35 36 ; CHECK: call i32 @_ZN1A3barEv( 37 %3 = load i32 (%struct.A*)*, i32 (%struct.A*)** %vfn4, align 8 38 39 %call5 = tail call i32 %3(%struct.A* %0) #1 40 br label %if.end 41 42 if.end: ; preds = %if.else, %if.then 43 ret void 44 } 45 46 ; Check integration with invariant.group handling 47 ; CHECK-LABEL: define void @invariantGroupHandling(i1 zeroext %p) { 48 define void @invariantGroupHandling(i1 zeroext %p) { 49 entry: 50 %call = tail call noalias i8* @_Znwm(i64 8) #4 51 %0 = bitcast i8* %call to %struct.A* 52 tail call void @_ZN1AC1Ev(%struct.A* %0) #1 53 %1 = bitcast i8* %call to i8*** 54 %vtable = load i8**, i8*** %1, align 8, !invariant.group !0 55 %cmp.vtables = icmp eq i8** %vtable, getelementptr inbounds ([4 x i8*], [4 x i8*]* @_ZTV1A, i64 0, i64 2) 56 tail call void @llvm.assume(i1 %cmp.vtables) 57 br i1 %p, label %if.then, label %if.else 58 59 if.then: ; preds = %entry 60 %vtable1.cast = bitcast i8** %vtable to i32 (%struct.A*)** 61 %2 = load i32 (%struct.A*)*, i32 (%struct.A*)** %vtable1.cast, align 8 62 63 ; CHECK: call i32 @_ZN1A3fooEv( 64 %call2 = tail call i32 %2(%struct.A* %0) #1 65 %vtable1 = load i8**, i8*** %1, align 8, !invariant.group !0 66 %vtable2.cast = bitcast i8** %vtable1 to i32 (%struct.A*)** 67 %call1 = load i32 (%struct.A*)*, i32 (%struct.A*)** %vtable2.cast, align 8 68 ; FIXME: those loads could be also direct, but right now the invariant.group 69 ; analysis works only on single block 70 ; CHECK-NOT: call i32 @_ZN1A3fooEv( 71 %callx = tail call i32 %call1(%struct.A* %0) #1 72 73 %vtable2 = load i8**, i8*** %1, align 8, !invariant.group !0 74 %vtable3.cast = bitcast i8** %vtable2 to i32 (%struct.A*)** 75 %call4 = load i32 (%struct.A*)*, i32 (%struct.A*)** %vtable3.cast, align 8 76 ; CHECK-NOT: call i32 @_ZN1A3fooEv( 77 %cally = tail call i32 %call4(%struct.A* %0) #1 78 79 %b = bitcast i8* %call to %struct.A** 80 %vtable3 = load %struct.A*, %struct.A** %b, align 8, !invariant.group !0 81 %vtable4.cast = bitcast %struct.A* %vtable3 to i32 (%struct.A*)** 82 %vfun = load i32 (%struct.A*)*, i32 (%struct.A*)** %vtable4.cast, align 8 83 ; CHECK-NOT: call i32 @_ZN1A3fooEv( 84 %unknown = tail call i32 %vfun(%struct.A* %0) #1 85 86 br label %if.end 87 88 if.else: ; preds = %entry 89 %vfn47 = getelementptr inbounds i8*, i8** %vtable, i64 1 90 %vfn4 = bitcast i8** %vfn47 to i32 (%struct.A*)** 91 92 ; CHECK: call i32 @_ZN1A3barEv( 93 %3 = load i32 (%struct.A*)*, i32 (%struct.A*)** %vfn4, align 8 94 95 %call5 = tail call i32 %3(%struct.A* %0) #1 96 br label %if.end 97 98 if.end: ; preds = %if.else, %if.then 99 ret void 100 } 101 102 103 ; Checking const propagation in the same BB 104 ; CHECK-LABEL: define i32 @main() 105 106 define i32 @main() { 107 entry: 108 %call = tail call noalias i8* @_Znwm(i64 8) 109 %0 = bitcast i8* %call to %struct.A* 110 tail call void @_ZN1AC1Ev(%struct.A* %0) 111 %1 = bitcast i8* %call to i8*** 112 %vtable = load i8**, i8*** %1, align 8 113 %cmp.vtables = icmp eq i8** %vtable, getelementptr inbounds ([4 x i8*], [4 x i8*]* @_ZTV1A, i64 0, i64 2) 114 tail call void @llvm.assume(i1 %cmp.vtables) 115 %vtable1.cast = bitcast i8** %vtable to i32 (%struct.A*)** 116 117 ; CHECK: call i32 @_ZN1A3fooEv( 118 %2 = load i32 (%struct.A*)*, i32 (%struct.A*)** %vtable1.cast, align 8 119 120 %call2 = tail call i32 %2(%struct.A* %0) 121 ret i32 0 122 } 123 124 ; This tests checks const propatation with fcmp instruction. 125 ; CHECK-LABEL: define float @_Z1gf(float %p) 126 127 define float @_Z1gf(float %p) { 128 entry: 129 %p.addr = alloca float, align 4 130 %f = alloca float, align 4 131 store float %p, float* %p.addr, align 4 132 133 store float 3.000000e+00, float* %f, align 4 134 %0 = load float, float* %p.addr, align 4 135 %1 = load float, float* %f, align 4 136 %cmp = fcmp oeq float %1, %0 ; note const on lhs 137 call void @llvm.assume(i1 %cmp) 138 139 ; CHECK: ret float 3.000000e+00 140 ret float %0 141 } 142 143 ; CHECK-LABEL: define float @_Z1hf(float %p) 144 145 define float @_Z1hf(float %p) { 146 entry: 147 %p.addr = alloca float, align 4 148 store float %p, float* %p.addr, align 4 149 150 %0 = load float, float* %p.addr, align 4 151 %cmp = fcmp nnan ueq float %0, 3.000000e+00 152 call void @llvm.assume(i1 %cmp) 153 154 ; CHECK: ret float 3.000000e+00 155 ret float %0 156 } 157 158 ; CHECK-LABEL: define float @_Z1if(float %p) 159 define float @_Z1if(float %p) { 160 entry: 161 %p.addr = alloca float, align 4 162 store float %p, float* %p.addr, align 4 163 164 %0 = load float, float* %p.addr, align 4 165 %cmp = fcmp ueq float %0, 3.000000e+00 ; no nnan flag - can't propagate 166 call void @llvm.assume(i1 %cmp) 167 168 ; CHECK-NOT: ret float 3.000000e+00 169 ret float %0 170 } 171 172 ; This test checks if constant propagation works for multiple node edges 173 ; CHECK-LABEL: define i32 @_Z1ii(i32 %p) 174 define i32 @_Z1ii(i32 %p) { 175 entry: 176 %cmp = icmp eq i32 %p, 42 177 call void @llvm.assume(i1 %cmp) 178 179 ; CHECK: br i1 true, label %bb2, label %bb2 180 br i1 %cmp, label %bb2, label %bb2 181 bb2: 182 call void @llvm.assume(i1 true) 183 ; CHECK: br i1 true, label %bb2, label %bb2 184 br i1 %cmp, label %bb2, label %bb2 185 186 ; CHECK: ret i32 42 187 ret i32 %p 188 } 189 190 ; CHECK-LABEL: define i32 @_Z1ij(i32 %p) 191 define i32 @_Z1ij(i32 %p) { 192 entry: 193 %cmp = icmp eq i32 %p, 42 194 call void @llvm.assume(i1 %cmp) 195 196 ; CHECK: br i1 true, label %bb2, label %bb2 197 br i1 %cmp, label %bb2, label %bb2 198 bb2: 199 ; CHECK-NOT: %cmp2 = 200 %cmp2 = icmp eq i32 %p, 42 201 ; CHECK-NOT: call void @llvm.assume( 202 call void @llvm.assume(i1 %cmp2) 203 204 ; CHECK: br i1 true, label %bb2, label %bb2 205 br i1 %cmp, label %bb2, label %bb2 206 207 ; CHECK: ret i32 42 208 ret i32 %p 209 } 210 211 ; CHECK-LABEL: define i32 @_Z1ik(i32 %p) 212 define i32 @_Z1ik(i32 %p) { 213 entry: 214 %cmp = icmp eq i32 %p, 42 215 call void @llvm.assume(i1 %cmp) 216 217 ; CHECK: br i1 true, label %bb2, label %bb3 218 br i1 %cmp, label %bb2, label %bb3 219 bb2: 220 ; CHECK-NOT: %cmp3 = 221 %cmp3 = icmp eq i32 %p, 43 222 ; CHECK: store i8 undef, i8* null 223 call void @llvm.assume(i1 %cmp3) 224 ret i32 15 225 bb3: 226 ret i32 17 227 } 228 229 declare noalias i8* @_Znwm(i64) 230 declare void @_ZN1AC1Ev(%struct.A*) 231 declare void @llvm.assume(i1) 232 declare i32 @_ZN1A3fooEv(%struct.A*) 233 declare i32 @_ZN1A3barEv(%struct.A*) 234 235 !0 = !{!"struct A"} 236
