1; RUN: opt < %s -basicaa -dse -S | FileCheck %s 2target datalayout = "E-p:64:64:64-a0:0:8-f32:32:32-f64:64:64-i1:8:8-i8:8:8-i16:16:16-i32:32:32-i64:32:64-v64:64:64-v128:128:128" 3 4declare void @llvm.memset.p0i8.i64(i8* nocapture, i8, i64, i32, i1) nounwind 5declare void @llvm.memcpy.p0i8.p0i8.i64(i8* nocapture, i8* nocapture, i64, i32, i1) nounwind 6declare i8* @llvm.init.trampoline(i8*, i8*, i8*) 7 8define void @test1(i32* %Q, i32* %P) { 9 %DEAD = load i32* %Q 10 store i32 %DEAD, i32* %P 11 store i32 0, i32* %P 12 ret void 13; CHECK: @test1 14; CHECK-NEXT: store i32 0, i32* %P 15; CHECK-NEXT: ret void 16} 17 18; PR8576 - Should delete store of 10 even though p/q are may aliases. 19define void @test2(i32 *%p, i32 *%q) { 20 store i32 10, i32* %p, align 4 21 store i32 20, i32* %q, align 4 22 store i32 30, i32* %p, align 4 23 ret void 24; CHECK: @test2 25; CHECK-NEXT: store i32 20 26} 27 28 29; PR8677 30@g = global i32 1 31 32define i32 @test3(i32* %g_addr) nounwind { 33; CHECK: @test3 34; CHECK: load i32* %g_addr 35 %g_value = load i32* %g_addr, align 4 36 store i32 -1, i32* @g, align 4 37 store i32 %g_value, i32* %g_addr, align 4 38 %tmp3 = load i32* @g, align 4 39 ret i32 %tmp3 40} 41 42 43define void @test4(i32* %Q) { 44 %a = load i32* %Q 45 store volatile i32 %a, i32* %Q 46 ret void 47; CHECK: @test4 48; CHECK-NEXT: load i32 49; CHECK-NEXT: store volatile 50; CHECK-NEXT: ret void 51} 52 53define void @test5(i32* %Q) { 54 %a = load volatile i32* %Q 55 store i32 %a, i32* %Q 56 ret void 57; CHECK: @test5 58; CHECK-NEXT: load volatile 59; CHECK-NEXT: ret void 60} 61 62; Should delete store of 10 even though memset is a may-store to P (P and Q may 63; alias). 64define void @test6(i32 *%p, i8 *%q) { 65 store i32 10, i32* %p, align 4 ;; dead. 66 call void @llvm.memset.p0i8.i64(i8* %q, i8 42, i64 900, i32 1, i1 false) 67 store i32 30, i32* %p, align 4 68 ret void 69; CHECK: @test6 70; CHECK-NEXT: call void @llvm.memset 71} 72 73; Should delete store of 10 even though memcpy is a may-store to P (P and Q may 74; alias). 75define void @test7(i32 *%p, i8 *%q, i8* noalias %r) { 76 store i32 10, i32* %p, align 4 ;; dead. 77 call void @llvm.memcpy.p0i8.p0i8.i64(i8* %q, i8* %r, i64 900, i32 1, i1 false) 78 store i32 30, i32* %p, align 4 79 ret void 80; CHECK: @test7 81; CHECK-NEXT: call void @llvm.memcpy 82} 83 84; Do not delete stores that are only partially killed. 85define i32 @test8() { 86 %V = alloca i32 87 store i32 1234567, i32* %V 88 %V2 = bitcast i32* %V to i8* 89 store i8 0, i8* %V2 90 %X = load i32* %V 91 ret i32 %X 92 93; CHECK: @test8 94; CHECK: store i32 1234567 95} 96 97 98; Test for byval handling. 99%struct.x = type { i32, i32, i32, i32 } 100define void @test9(%struct.x* byval %a) nounwind { 101 %tmp2 = getelementptr %struct.x* %a, i32 0, i32 0 102 store i32 1, i32* %tmp2, align 4 103 ret void 104; CHECK: @test9 105; CHECK-NEXT: ret void 106} 107 108; va_arg has fuzzy dependence, the store shouldn't be zapped. 109define double @test10(i8* %X) { 110 %X_addr = alloca i8* 111 store i8* %X, i8** %X_addr 112 %tmp.0 = va_arg i8** %X_addr, double 113 ret double %tmp.0 114; CHECK: @test10 115; CHECK: store 116} 117 118 119; DSE should delete the dead trampoline. 120declare void @test11f() 121define void @test11() { 122; CHECK: @test11 123 %storage = alloca [10 x i8], align 16 ; <[10 x i8]*> [#uses=1] 124; CHECK-NOT: alloca 125 %cast = getelementptr [10 x i8]* %storage, i32 0, i32 0 ; <i8*> [#uses=1] 126 %tramp = call i8* @llvm.init.trampoline( i8* %cast, i8* bitcast (void ()* @test11f to i8*), i8* null ) ; <i8*> [#uses=1] 127; CHECK-NOT: trampoline 128 ret void 129; CHECK: ret void 130} 131 132 133; PR2599 - load -> store to same address. 134define void @test12({ i32, i32 }* %x) nounwind { 135 %tmp4 = getelementptr { i32, i32 }* %x, i32 0, i32 0 136 %tmp5 = load i32* %tmp4, align 4 137 %tmp7 = getelementptr { i32, i32 }* %x, i32 0, i32 1 138 %tmp8 = load i32* %tmp7, align 4 139 %tmp17 = sub i32 0, %tmp8 140 store i32 %tmp5, i32* %tmp4, align 4 141 store i32 %tmp17, i32* %tmp7, align 4 142 ret void 143; CHECK: @test12 144; CHECK-NOT: tmp5 145; CHECK: ret void 146} 147 148 149; %P doesn't escape, the DEAD instructions should be removed. 150declare void @test13f() 151define i32* @test13() { 152 %p = tail call i8* @malloc(i32 4) 153 %P = bitcast i8* %p to i32* 154 %DEAD = load i32* %P 155 %DEAD2 = add i32 %DEAD, 1 156 store i32 %DEAD2, i32* %P 157 call void @test13f( ) 158 store i32 0, i32* %P 159 ret i32* %P 160; CHECK: @test13() 161; CHECK-NEXT: malloc 162; CHECK-NEXT: bitcast 163; CHECK-NEXT: call void 164} 165 166declare noalias i8* @malloc(i32) 167 168 169 170define void @test14(i32* %Q) { 171 %P = alloca i32 172 %DEAD = load i32* %Q 173 store i32 %DEAD, i32* %P 174 ret void 175 176; CHECK: @test14 177; CHECK-NEXT: ret void 178} 179 180 181; PR8701 182 183;; Fully dead overwrite of memcpy. 184define void @test15(i8* %P, i8* %Q) nounwind ssp { 185 tail call void @llvm.memcpy.p0i8.p0i8.i64(i8* %P, i8* %Q, i64 12, i32 1, i1 false) 186 tail call void @llvm.memcpy.p0i8.p0i8.i64(i8* %P, i8* %Q, i64 12, i32 1, i1 false) 187 ret void 188; CHECK: @test15 189; CHECK-NEXT: call void @llvm.memcpy 190; CHECK-NEXT: ret 191} 192 193;; Full overwrite of smaller memcpy. 194define void @test16(i8* %P, i8* %Q) nounwind ssp { 195 tail call void @llvm.memcpy.p0i8.p0i8.i64(i8* %P, i8* %Q, i64 8, i32 1, i1 false) 196 tail call void @llvm.memcpy.p0i8.p0i8.i64(i8* %P, i8* %Q, i64 12, i32 1, i1 false) 197 ret void 198; CHECK: @test16 199; CHECK-NEXT: call void @llvm.memcpy 200; CHECK-NEXT: ret 201} 202 203;; Overwrite of memset by memcpy. 204define void @test17(i8* %P, i8* noalias %Q) nounwind ssp { 205 tail call void @llvm.memset.p0i8.i64(i8* %P, i8 42, i64 8, i32 1, i1 false) 206 tail call void @llvm.memcpy.p0i8.p0i8.i64(i8* %P, i8* %Q, i64 12, i32 1, i1 false) 207 ret void 208; CHECK: @test17 209; CHECK-NEXT: call void @llvm.memcpy 210; CHECK-NEXT: ret 211} 212 213; Should not delete the volatile memset. 214define void @test17v(i8* %P, i8* %Q) nounwind ssp { 215 tail call void @llvm.memset.p0i8.i64(i8* %P, i8 42, i64 8, i32 1, i1 true) 216 tail call void @llvm.memcpy.p0i8.p0i8.i64(i8* %P, i8* %Q, i64 12, i32 1, i1 false) 217 ret void 218; CHECK: @test17v 219; CHECK-NEXT: call void @llvm.memset 220; CHECK-NEXT: call void @llvm.memcpy 221; CHECK-NEXT: ret 222} 223 224; PR8728 225; Do not delete instruction where possible situation is: 226; A = B 227; A = A 228define void @test18(i8* %P, i8* %Q, i8* %R) nounwind ssp { 229 tail call void @llvm.memcpy.p0i8.p0i8.i64(i8* %P, i8* %Q, i64 12, i32 1, i1 false) 230 tail call void @llvm.memcpy.p0i8.p0i8.i64(i8* %P, i8* %R, i64 12, i32 1, i1 false) 231 ret void 232; CHECK: @test18 233; CHECK-NEXT: call void @llvm.memcpy 234; CHECK-NEXT: call void @llvm.memcpy 235; CHECK-NEXT: ret 236} 237 238 239; The store here is not dead because the byval call reads it. 240declare void @test19f({i32}* byval align 4 %P) 241 242define void @test19({i32} * nocapture byval align 4 %arg5) nounwind ssp { 243bb: 244 %tmp7 = getelementptr inbounds {i32}* %arg5, i32 0, i32 0 245 store i32 912, i32* %tmp7 246 call void @test19f({i32}* byval align 4 %arg5) 247 ret void 248 249; CHECK: @test19( 250; CHECK: store i32 912 251; CHECK: call void @test19f 252} 253 254