75 lines · plain
1; RUN: opt -O2 %s | llvm-dis > %t12; RUN: llc -filetype=asm -o - %t1 | FileCheck %s3; RUN: llc -mattr=+alu32 -filetype=asm -o - %t1 | FileCheck %s4;5; Source code:6; union u { int a; int b; };7; #define _(x) (__builtin_preserve_access_index(x))8; int get_value(const ptr addr);9; int test(union u *arg) { return get_value(_(&arg->b)); }10; Compiler flag to generate IR:11; clang -target bpf -S -O2 -g -emit-llvm -Xclang -disable-llvm-passes test.c12 13target triple = "bpf"14 15%union.u = type { i32 }16 17; Function Attrs: nounwind18define dso_local i32 @test(ptr %arg) local_unnamed_addr !dbg !7 {19entry:20 call void @llvm.dbg.value(metadata ptr %arg, metadata !17, metadata !DIExpression()), !dbg !1821 %0 = tail call ptr @llvm.preserve.union.access.index.p0.us.p0.us(ptr %arg, i32 1), !dbg !19, !llvm.preserve.access.index !1222 %call = tail call i32 @get_value(ptr %0), !dbg !2023 ret i32 %call, !dbg !2124}25; CHECK-LABEL: test26; CHECK: [[RELOC:.Ltmp[0-9]+]]27; CHECK: r2 = 028; CHECK: r1 += r229; CHECK: call get_value30; CHECK: exit31 32; CHECK: .section .BTF.ext,"",@progbits33; CHECK: .long 16 # FieldReloc34; CHECK-NEXT: .long 20 # Field reloc section string offset=2035; CHECK-NEXT: .long 136; CHECK-NEXT: .long [[RELOC]]37; CHECK-NEXT: .long 238; CHECK-NEXT: .long 2639; CHECK-NEXT: .long 040 41declare dso_local i32 @get_value(ptr) local_unnamed_addr42 43; Function Attrs: nounwind readnone44declare ptr @llvm.preserve.union.access.index.p0.us.p0.us(ptr, i32 immarg)45 46; Function Attrs: nounwind readnone speculatable47declare void @llvm.dbg.value(metadata, metadata, metadata)48 49!llvm.dbg.cu = !{!0}50!llvm.module.flags = !{!3, !4, !5}51!llvm.ident = !{!6}52 53!0 = distinct !DICompileUnit(language: DW_LANG_C99, file: !1, producer: "clang version 9.0.0 (trunk 365789)", isOptimized: true, runtimeVersion: 0, emissionKind: FullDebug, enums: !2, nameTableKind: None)54!1 = !DIFile(filename: "test.c", directory: "/tmp/home/yhs/work/tests/core")55!2 = !{}56!3 = !{i32 2, !"Dwarf Version", i32 4}57!4 = !{i32 2, !"Debug Info Version", i32 3}58!5 = !{i32 1, !"wchar_size", i32 4}59!6 = !{!"clang version 9.0.0 (trunk 365789)"}60!7 = distinct !DISubprogram(name: "test", scope: !1, file: !1, line: 4, type: !8, scopeLine: 4, flags: DIFlagPrototyped, spFlags: DISPFlagDefinition | DISPFlagOptimized, unit: !0, retainedNodes: !16)61!8 = !DISubroutineType(types: !9)62!9 = !{!10, !11}63!10 = !DIBasicType(name: "int", size: 32, encoding: DW_ATE_signed)64!11 = !DIDerivedType(tag: DW_TAG_pointer_type, baseType: !12, size: 64)65!12 = distinct !DICompositeType(tag: DW_TAG_union_type, name: "u", file: !1, line: 1, size: 32, elements: !13)66!13 = !{!14, !15}67!14 = !DIDerivedType(tag: DW_TAG_member, name: "a", scope: !12, file: !1, line: 1, baseType: !10, size: 32)68!15 = !DIDerivedType(tag: DW_TAG_member, name: "b", scope: !12, file: !1, line: 1, baseType: !10, size: 32)69!16 = !{!17}70!17 = !DILocalVariable(name: "arg", arg: 1, scope: !7, file: !1, line: 4, type: !11)71!18 = !DILocation(line: 0, scope: !7)72!19 = !DILocation(line: 4, column: 43, scope: !7)73!20 = !DILocation(line: 4, column: 33, scope: !7)74!21 = !DILocation(line: 4, column: 26, scope: !7)75