; RUN: opt < %s -passes=add-discriminators,sroa -S | FileCheck %s target datalayout = "e-m:e-i64:64-f80:128-n8:16:32:64-S128" ; Test case obtained from the following C code: ; struct A { ; int field1; ; short field2; ; }; ; ; struct B { ; struct A field1; ; int field2; ; }; ; ; ; extern struct B g_b; ; extern int bar(struct B b, int c); ; ; int foo(int cond) { ; int result = cond ? bar(g_b, 33) : 42; ; return result; ; } ; In this test, global variable g_b is passed by copy to function bar. That ; copy is located on the stack (see alloca %g_b.coerce), and it is initialized ; by a memcpy call. ; ; SROA would split alloca %g_b.coerce into two (smaller disjoint) slices: ; slice [0,8) and slice [8, 12). Users of the original alloca are rewritten ; as users of the new alloca slices. ; In particular, the memcpy is rewritten by SROA as two load/store pairs. ; ; Later on, mem2reg successfully promotes the new alloca slices to registers, ; and loads %3 and %5 are made redundant by the loads obtained from the memcpy ; intrinsic expansion. ; ; If pass AddDiscriminators doesn't assign a discriminator to the intrinsic ; memcpy call, then the loads obtained from the memcpy expansion would not have ; a correct discriminator. ; ; This test checks that the two new loads inserted by SROA in %cond.true ; correctly reference a debug location with a non-zero discriminator. This test ; also checks that the same discriminator is used by all instructions from ; basic block %cond.true. %struct.B = type { %struct.A, i32 } %struct.A = type { i32, i16 } @g_b = external global %struct.B, align 4 define i32 @foo(i32 %cond) #0 !dbg !5 { entry: %g_b.coerce = alloca { i64, i32 }, align 4 %tobool = icmp ne i32 %cond, 0, !dbg !7 br i1 %tobool, label %cond.true, label %cond.end, !dbg !7 cond.true: ; CHECK-LABEL: cond.true: ; CHECK: load i64, {{.*}}, !dbg ![[LOC:[0-9]+]] ; CHECK-NEXT: load i32, {{.*}}, !dbg ![[LOC]] ; CHECK-NEXT: %call = call i32 @bar({{.*}}), !dbg ![[LOC]] ; CHECK-NEXT: br label %cond.end, !dbg ![[BR_LOC:[0-9]+]] ; CHECK-DAG: ![[LOC]] = !DILocation(line: 16, column: 23, scope: ![[SCOPE:[0-9]+]]) ; CHECK-DAG: ![[SCOPE]] = !DILexicalBlockFile({{.*}}, discriminator: 2) ; CHECK-DAG: ![[BR_LOC]] = !DILocation(line: 16, column: 16, scope: ![[SCOPE]]) call void @llvm.memcpy.p0.p0.i64(ptr align 4 %g_b.coerce, ptr align 4 @g_b, i64 12, i1 false), !dbg !8 %p1 = getelementptr inbounds { i64, i32 }, ptr %g_b.coerce, i32 0, i32 0, !dbg !8 %v1 = load i64, ptr %p1, align 4, !dbg !8 %p2 = getelementptr inbounds { i64, i32 }, ptr %g_b.coerce, i32 0, i32 1, !dbg !8 %v2 = load i32, ptr %p2, align 4, !dbg !8 %call = call i32 @bar(i64 %v1, i32 %v2, i32 33), !dbg !8 br label %cond.end, !dbg !7 cond.end: ; preds = %entry, %cond.true %cond1 = phi i32 [ %call, %cond.true ], [ 42, %entry ], !dbg !7 ret i32 %cond1, !dbg !9 } declare i32 @bar(i64, i32, i32) declare void @llvm.memcpy.p0.p0.i64(ptr nocapture writeonly, ptr nocapture readonly, i64, i1) #1 attributes #0 = { noinline nounwind uwtable } attributes #1 = { argmemonly nounwind } !llvm.dbg.cu = !{!0} !llvm.module.flags = !{!3, !4} !0 = distinct !DICompileUnit(language: DW_LANG_C99, file: !1, isOptimized: false, runtimeVersion: 0, emissionKind: LineTablesOnly, enums: !2) !1 = !DIFile(filename: "test.c", directory: ".") !2 = !{} !3 = !{i32 2, !"Dwarf Version", i32 4} !4 = !{i32 2, !"Debug Info Version", i32 3} !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) !6 = !DISubroutineType(types: !2) !7 = !DILocation(line: 16, column: 16, scope: !5) !8 = !DILocation(line: 16, column: 23, scope: !5) !9 = !DILocation(line: 17, column: 3, scope: !5)