; RUN: llc -O2 -march=bpf -mcpu=v3 < %s | FileCheck %s ; Source code: ; struct t3 { ; int i; ; } __attribute__((preserve_access_index)); ; struct t2 { ; void *pad; ; struct t3 *f; ; } __attribute__((preserve_access_index)); ; struct t1 { ; void *pad; ; struct t2 *q; ; } __attribute__((preserve_access_index)); ; ; int g; ; int test(struct t1 *p) { ; struct t2 *q = p->q; ; if (q) ; return 0; ; struct t3 *f = q->f; ; if (!f) g = 5; ; return 0; ; } ; Compilation flag: ; clang -target bpf -O2 -g -S -emit-llvm t.c @g = dso_local local_unnamed_addr global i32 0, align 4, !dbg !0 @"llvm.t2:0:8$0:1" = external global i64, !llvm.preserve.access.index !6 #0 @"llvm.t1:0:8$0:1" = external global i64, !llvm.preserve.access.index !15 #0 ; Function Attrs: mustprogress nofree nosync nounwind willreturn define dso_local i32 @test(ptr noundef readonly %p) local_unnamed_addr #1 !dbg !25 { entry: call void @llvm.dbg.value(metadata ptr %p, metadata !30, metadata !DIExpression()), !dbg !33 %0 = load i64, ptr @"llvm.t1:0:8$0:1", align 8 %1 = getelementptr i8, ptr %p, i64 %0 %2 = tail call ptr @llvm.bpf.passthrough.p0.p0(i32 1, ptr %1) %3 = load ptr, ptr %2, align 8, !dbg !34, !tbaa !35 call void @llvm.dbg.value(metadata ptr %3, metadata !31, metadata !DIExpression()), !dbg !33 %tobool.not = icmp eq ptr %3, null, !dbg !40 br i1 %tobool.not, label %if.end, label %cleanup, !dbg !42 ; CHECK-LABEL: test ; CHECK: r1 = *(u64 *)(r1 + 8) ; CHECK: if r1 != 0 goto if.end: ; preds = %entry %4 = load i64, ptr @"llvm.t2:0:8$0:1", align 8 %5 = getelementptr i8, ptr null, i64 %4 %6 = tail call ptr @llvm.bpf.passthrough.p0.p0(i32 0, ptr %5) %7 = load ptr, ptr %6, align 8, !dbg !43, !tbaa !44 call void @llvm.dbg.value(metadata ptr %7, metadata !32, metadata !DIExpression()), !dbg !33 %tobool1.not = icmp eq ptr %7, null, !dbg !46 br i1 %tobool1.not, label %if.then2, label %cleanup, !dbg !48 ; CHECK: r1 = 8 ; CHECK: r1 = *(u64 *)(r1 + 0) ; CHECK: if r1 != 0 goto if.then2: ; preds = %if.end store i32 5, ptr @g, align 4, !dbg !49, !tbaa !50 br label %cleanup, !dbg !52 cleanup: ; preds = %if.end, %if.then2, %entry ret i32 0, !dbg !53 } ; Function Attrs: nofree nosync nounwind readnone declare ptr @llvm.bpf.passthrough.p0.p0(i32, ptr) #2 ; Function Attrs: nocallback nofree nosync nounwind readnone speculatable willreturn declare void @llvm.dbg.value(metadata, metadata, metadata) #3 attributes #0 = { "btf_ama" } attributes #1 = { mustprogress nofree nosync nounwind willreturn "frame-pointer"="all" "min-legal-vector-width"="0" "no-trapping-math"="true" "stack-protector-buffer-size"="8" } attributes #2 = { nofree nosync nounwind readnone } attributes #3 = { nocallback nofree nosync nounwind readnone speculatable willreturn } !llvm.dbg.cu = !{!2} !llvm.module.flags = !{!20, !21, !22, !23} !llvm.ident = !{!24} !0 = !DIGlobalVariableExpression(var: !1, expr: !DIExpression()) !1 = distinct !DIGlobalVariable(name: "g", scope: !2, file: !3, line: 13, type: !5, isLocal: false, isDefinition: true) !2 = distinct !DICompileUnit(language: DW_LANG_C99, file: !3, producer: "clang version 15.0.0 (https://github.com/llvm/llvm-project.git ca2be81e34a6d87edb8e555dfac94ab68ee20f70)", isOptimized: true, runtimeVersion: 0, emissionKind: FullDebug, globals: !4, splitDebugInlining: false, nameTableKind: None) !3 = !DIFile(filename: "t.c", directory: "/tmp/home/yhs/work/tests/llvm/nullptr", checksumkind: CSK_MD5, checksum: "2c0ea9b3c647baf31f56992f9142b0df") !4 = !{!0} !5 = !DIBasicType(name: "int", size: 32, encoding: DW_ATE_signed) !6 = distinct !DICompositeType(tag: DW_TAG_structure_type, name: "t2", file: !3, line: 4, size: 128, elements: !7) !7 = !{!8, !10} !8 = !DIDerivedType(tag: DW_TAG_member, name: "pad", scope: !6, file: !3, line: 5, baseType: !9, size: 64) !9 = !DIDerivedType(tag: DW_TAG_pointer_type, baseType: null, size: 64) !10 = !DIDerivedType(tag: DW_TAG_member, name: "f", scope: !6, file: !3, line: 6, baseType: !11, size: 64, offset: 64) !11 = !DIDerivedType(tag: DW_TAG_pointer_type, baseType: !12, size: 64) !12 = distinct !DICompositeType(tag: DW_TAG_structure_type, name: "t3", file: !3, line: 1, size: 32, elements: !13) !13 = !{!14} !14 = !DIDerivedType(tag: DW_TAG_member, name: "i", scope: !12, file: !3, line: 2, baseType: !5, size: 32) !15 = distinct !DICompositeType(tag: DW_TAG_structure_type, name: "t1", file: !3, line: 8, size: 128, elements: !16) !16 = !{!17, !18} !17 = !DIDerivedType(tag: DW_TAG_member, name: "pad", scope: !15, file: !3, line: 9, baseType: !9, size: 64) !18 = !DIDerivedType(tag: DW_TAG_member, name: "q", scope: !15, file: !3, line: 10, baseType: !19, size: 64, offset: 64) !19 = !DIDerivedType(tag: DW_TAG_pointer_type, baseType: !6, size: 64) !20 = !{i32 7, !"Dwarf Version", i32 5} !21 = !{i32 2, !"Debug Info Version", i32 3} !22 = !{i32 1, !"wchar_size", i32 4} !23 = !{i32 7, !"frame-pointer", i32 2} !24 = !{!"clang version 15.0.0 (https://github.com/llvm/llvm-project.git ca2be81e34a6d87edb8e555dfac94ab68ee20f70)"} !25 = distinct !DISubprogram(name: "test", scope: !3, file: !3, line: 14, type: !26, scopeLine: 14, flags: DIFlagPrototyped | DIFlagAllCallsDescribed, spFlags: DISPFlagDefinition | DISPFlagOptimized, unit: !2, retainedNodes: !29) !26 = !DISubroutineType(types: !27) !27 = !{!5, !28} !28 = !DIDerivedType(tag: DW_TAG_pointer_type, baseType: !15, size: 64) !29 = !{!30, !31, !32} !30 = !DILocalVariable(name: "p", arg: 1, scope: !25, file: !3, line: 14, type: !28) !31 = !DILocalVariable(name: "q", scope: !25, file: !3, line: 15, type: !19) !32 = !DILocalVariable(name: "f", scope: !25, file: !3, line: 18, type: !11) !33 = !DILocation(line: 0, scope: !25) !34 = !DILocation(line: 15, column: 21, scope: !25) !35 = !{!36, !37, i64 8} !36 = !{!"t1", !37, i64 0, !37, i64 8} !37 = !{!"any pointer", !38, i64 0} !38 = !{!"omnipotent char", !39, i64 0} !39 = !{!"Simple C/C++ TBAA"} !40 = !DILocation(line: 16, column: 7, scope: !41) !41 = distinct !DILexicalBlock(scope: !25, file: !3, line: 16, column: 7) !42 = !DILocation(line: 16, column: 7, scope: !25) !43 = !DILocation(line: 18, column: 21, scope: !25) !44 = !{!45, !37, i64 8} !45 = !{!"t2", !37, i64 0, !37, i64 8} !46 = !DILocation(line: 19, column: 8, scope: !47) !47 = distinct !DILexicalBlock(scope: !25, file: !3, line: 19, column: 7) !48 = !DILocation(line: 19, column: 7, scope: !25) !49 = !DILocation(line: 19, column: 13, scope: !47) !50 = !{!51, !51, i64 0} !51 = !{!"int", !38, i64 0} !52 = !DILocation(line: 19, column: 11, scope: !47) !53 = !DILocation(line: 21, column: 1, scope: !25)