1; RUN: opt < %s -passes='add-discriminators,sroa' -S | FileCheck %s 2 3target datalayout = "e-m:e-i64:64-f80:128-n8:16:32:64-S128" 4 5; Test case obtained from the following C code: 6 7; struct A { 8; int field1; 9; short field2; 10; }; 11; 12; struct B { 13; struct A field1; 14; int field2; 15; }; 16; 17; 18; extern struct B g_b; 19; extern int bar(struct B b, int c); 20; 21; int foo(int cond) { 22; int result = cond ? bar(g_b, 33) : 42; 23; return result; 24; } 25 26; In this test, global variable g_b is passed by copy to function bar. That 27; copy is located on the stack (see alloca %g_b.coerce), and it is initialized 28; by a memcpy call. 29; 30; SROA would split alloca %g_b.coerce into two (smaller disjoint) slices: 31; slice [0,8) and slice [8, 12). Users of the original alloca are rewritten 32; as users of the new alloca slices. 33; In particular, the memcpy is rewritten by SROA as two load/store pairs. 34; 35; Later on, mem2reg successfully promotes the new alloca slices to registers, 36; and loads %3 and %5 are made redundant by the loads obtained from the memcpy 37; intrinsic expansion. 38; 39; If pass AddDiscriminators doesn't assign a discriminator to the intrinsic 40; memcpy call, then the loads obtained from the memcpy expansion would not have 41; a correct discriminator. 42; 43; This test checks that the two new loads inserted by SROA in %cond.true 44; correctly reference a debug location with a non-zero discriminator. This test 45; also checks that the same discriminator is used by all instructions from 46; basic block %cond.true. 47 48%struct.B = type { %struct.A, i32 } 49%struct.A = type { i32, i16 } 50 51@g_b = external global %struct.B, align 4 52 53define i32 @foo(i32 %cond) #0 !dbg !5 { 54entry: 55 %g_b.coerce = alloca { i64, i32 }, align 4 56 %tobool = icmp ne i32 %cond, 0, !dbg !7 57 br i1 %tobool, label %cond.true, label %cond.end, !dbg !7 58 59cond.true: 60; CHECK-LABEL: cond.true: 61; CHECK: load i64, {{.*}}, !dbg ![[LOC:[0-9]+]] 62; CHECK-NEXT: load i32, {{.*}}, !dbg ![[LOC]] 63; CHECK-NEXT: %call = call i32 @bar({{.*}}), !dbg ![[LOC]] 64; CHECK-NEXT: br label %cond.end, !dbg ![[BR_LOC:[0-9]+]] 65 66; CHECK-DAG: ![[LOC]] = !DILocation(line: 16, column: 23, scope: ![[SCOPE:[0-9]+]]) 67; CHECK-DAG: ![[SCOPE]] = !DILexicalBlockFile({{.*}}, discriminator: 2) 68; CHECK-DAG: ![[BR_LOC]] = !DILocation(line: 16, column: 16, scope: ![[SCOPE]]) 69 70 call void @llvm.memcpy.p0.p0.i64(ptr align 4 %g_b.coerce, ptr align 4 @g_b, i64 12, i1 false), !dbg !8 71 %p1 = getelementptr inbounds { i64, i32 }, ptr %g_b.coerce, i32 0, i32 0, !dbg !8 72 %v1 = load i64, ptr %p1, align 4, !dbg !8 73 %p2 = getelementptr inbounds { i64, i32 }, ptr %g_b.coerce, i32 0, i32 1, !dbg !8 74 %v2 = load i32, ptr %p2, align 4, !dbg !8 75 %call = call i32 @bar(i64 %v1, i32 %v2, i32 33), !dbg !8 76 br label %cond.end, !dbg !7 77 78cond.end: ; preds = %entry, %cond.true 79 %cond1 = phi i32 [ %call, %cond.true ], [ 42, %entry ], !dbg !7 80 ret i32 %cond1, !dbg !9 81} 82 83declare i32 @bar(i64, i32, i32) 84 85declare void @llvm.memcpy.p0.p0.i64(ptr nocapture writeonly, ptr nocapture readonly, i64, i1) #1 86 87attributes #0 = { noinline nounwind uwtable } 88attributes #1 = { argmemonly nounwind } 89 90!llvm.dbg.cu = !{!0} 91!llvm.module.flags = !{!3, !4} 92 93!0 = distinct !DICompileUnit(language: DW_LANG_C99, file: !1, isOptimized: false, runtimeVersion: 0, emissionKind: LineTablesOnly, enums: !2) 94!1 = !DIFile(filename: "test.c", directory: ".") 95!2 = !{} 96!3 = !{i32 2, !"Dwarf Version", i32 4} 97!4 = !{i32 2, !"Debug Info Version", i32 3} 98!5 = distinct !DISubprogram(name: "foo", scope: !1, file: !1, line: 15, type: !6, isLocal: false, isDefinition: true, scopeLine: 15, flags: DIFlagPrototyped, isOptimized: false, unit: !0, retainedNodes: !2) 99!6 = !DISubroutineType(types: !2) 100!7 = !DILocation(line: 16, column: 16, scope: !5) 101!8 = !DILocation(line: 16, column: 23, scope: !5) 102!9 = !DILocation(line: 17, column: 3, scope: !5) 103