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|
; RUN: opt -O2 %s | llvm-dis > %t1
; RUN: llc -filetype=asm -o - %t1 | FileCheck -check-prefixes=CHECK,CHECK-EL,CHECK64 %s
; RUN: llc -mattr=+alu32 -filetype=asm -o - %t1 | FileCheck -check-prefixes=CHECK,CHECK-EL,CHECK32 %s
; Source code:
; struct s {
; int a;
; int b1:9;
; int b2:4;
; };
; enum {
; FIELD_BYTE_OFFSET = 0,
; FIELD_BYTE_SIZE,
; FIELD_EXISTENCE,
; FIELD_SIGNEDNESS,
; FIELD_LSHIFT_U64,
; FIELD_RSHIFT_U64,
; };
; int field_read(struct s *arg) {
; unsigned long long ull;
; unsigned offset = __builtin_preserve_field_info(arg->b2, FIELD_BYTE_OFFSET);
; unsigned size = __builtin_preserve_field_info(arg->b2, FIELD_BYTE_SIZE);
; switch(size) {
; case 1:
; ull = *(unsigned char *)((void *)arg + offset); break;
; case 2:
; ull = *(unsigned short *)((void *)arg + offset); break;
; case 4:
; ull = *(unsigned int *)((void *)arg + offset); break;
; case 8:
; ull = *(unsigned long long *)((void *)arg + offset); break;
; }
; ull <<= __builtin_preserve_field_info(arg->b2, FIELD_LSHIFT_U64);
; if (__builtin_preserve_field_info(arg->b2, FIELD_SIGNEDNESS))
; return ((long long)ull) >>__builtin_preserve_field_info(arg->b2, FIELD_RSHIFT_U64);
; return ull >> __builtin_preserve_field_info(arg->b2, FIELD_RSHIFT_U64);
; }
; Compilation flag:
; clang -target bpfel -O2 -g -S -emit-llvm -Xclang -disable-llvm-passes test.c
target triple = "bpfel"
%struct.s = type { i32, i16 }
; Function Attrs: nounwind readonly
define dso_local i32 @field_read(%struct.s* %arg) local_unnamed_addr #0 !dbg !26 {
entry:
call void @llvm.dbg.value(metadata %struct.s* %arg, metadata !37, metadata !DIExpression()), !dbg !41
%0 = tail call i16* @llvm.preserve.struct.access.index.p0i16.p0s_struct.ss(%struct.s* elementtype(%struct.s) %arg, i32 1, i32 2), !dbg !42, !llvm.preserve.access.index !31
%1 = tail call i32 @llvm.bpf.preserve.field.info.p0i16(i16* %0, i64 0), !dbg !43
call void @llvm.dbg.value(metadata i32 %1, metadata !39, metadata !DIExpression()), !dbg !41
%2 = tail call i32 @llvm.bpf.preserve.field.info.p0i16(i16* %0, i64 1), !dbg !44
call void @llvm.dbg.value(metadata i32 %2, metadata !40, metadata !DIExpression()), !dbg !41
switch i32 %2, label %sw.epilog [
i32 1, label %sw.bb
i32 2, label %sw.bb1
i32 4, label %sw.bb5
i32 8, label %sw.bb9
], !dbg !45
sw.bb: ; preds = %entry
%3 = bitcast %struct.s* %arg to i8*, !dbg !46
%idx.ext = zext i32 %1 to i64, !dbg !48
%add.ptr = getelementptr i8, i8* %3, i64 %idx.ext, !dbg !48
%4 = load i8, i8* %add.ptr, align 1, !dbg !49, !tbaa !50
%conv = zext i8 %4 to i64, !dbg !49
call void @llvm.dbg.value(metadata i64 %conv, metadata !38, metadata !DIExpression()), !dbg !41
br label %sw.epilog, !dbg !53
sw.bb1: ; preds = %entry
%5 = bitcast %struct.s* %arg to i8*, !dbg !54
%idx.ext2 = zext i32 %1 to i64, !dbg !55
%add.ptr3 = getelementptr i8, i8* %5, i64 %idx.ext2, !dbg !55
%6 = bitcast i8* %add.ptr3 to i16*, !dbg !56
%7 = load i16, i16* %6, align 2, !dbg !57, !tbaa !58
%conv4 = zext i16 %7 to i64, !dbg !57
call void @llvm.dbg.value(metadata i64 %conv4, metadata !38, metadata !DIExpression()), !dbg !41
br label %sw.epilog, !dbg !60
sw.bb5: ; preds = %entry
%8 = bitcast %struct.s* %arg to i8*, !dbg !61
%idx.ext6 = zext i32 %1 to i64, !dbg !62
%add.ptr7 = getelementptr i8, i8* %8, i64 %idx.ext6, !dbg !62
%9 = bitcast i8* %add.ptr7 to i32*, !dbg !63
%10 = load i32, i32* %9, align 4, !dbg !64, !tbaa !65
%conv8 = zext i32 %10 to i64, !dbg !64
call void @llvm.dbg.value(metadata i64 %conv8, metadata !38, metadata !DIExpression()), !dbg !41
br label %sw.epilog, !dbg !67
sw.bb9: ; preds = %entry
%11 = bitcast %struct.s* %arg to i8*, !dbg !68
%idx.ext10 = zext i32 %1 to i64, !dbg !69
%add.ptr11 = getelementptr i8, i8* %11, i64 %idx.ext10, !dbg !69
%12 = bitcast i8* %add.ptr11 to i64*, !dbg !70
%13 = load i64, i64* %12, align 8, !dbg !71, !tbaa !72
call void @llvm.dbg.value(metadata i64 %13, metadata !38, metadata !DIExpression()), !dbg !41
br label %sw.epilog, !dbg !74
sw.epilog: ; preds = %entry, %sw.bb9, %sw.bb5, %sw.bb1, %sw.bb
%ull.0 = phi i64 [ undef, %entry ], [ %13, %sw.bb9 ], [ %conv8, %sw.bb5 ], [ %conv4, %sw.bb1 ], [ %conv, %sw.bb ]
call void @llvm.dbg.value(metadata i64 %ull.0, metadata !38, metadata !DIExpression()), !dbg !41
%14 = tail call i32 @llvm.bpf.preserve.field.info.p0i16(i16* %0, i64 4), !dbg !75
%sh_prom = zext i32 %14 to i64, !dbg !76
%shl = shl i64 %ull.0, %sh_prom, !dbg !76
call void @llvm.dbg.value(metadata i64 %shl, metadata !38, metadata !DIExpression()), !dbg !41
%15 = tail call i32 @llvm.bpf.preserve.field.info.p0i16(i16* %0, i64 3), !dbg !77
%tobool = icmp eq i32 %15, 0, !dbg !77
%16 = tail call i32 @llvm.bpf.preserve.field.info.p0i16(i16* %0, i64 5), !dbg !41
%sh_prom12 = zext i32 %16 to i64, !dbg !41
%shr = ashr i64 %shl, %sh_prom12, !dbg !79
%shr15 = lshr i64 %shl, %sh_prom12, !dbg !79
%retval.0.in = select i1 %tobool, i64 %shr15, i64 %shr, !dbg !79
%retval.0 = trunc i64 %retval.0.in to i32, !dbg !41
ret i32 %retval.0, !dbg !80
}
; CHECK: r{{[0-9]+}} = 4
; CHECK: r{{[0-9]+}} = 4
; CHECK-EL: r{{[0-9]+}} <<= 51
; CHECK64: r{{[0-9]+}} s>>= 60
; CHECK64: r{{[0-9]+}} >>= 60
; CHECK32: r{{[0-9]+}} >>= 60
; CHECK32: r{{[0-9]+}} s>>= 60
; CHECK: r{{[0-9]+}} = 1
; CHECK: .long 1 # BTF_KIND_STRUCT(id = 2)
; CHECK: .byte 115 # string offset=1
; CHECK: .ascii ".text" # string offset=30
; CHECK: .ascii "0:2" # string offset=36
; CHECK: .long 16 # FieldReloc
; CHECK-NEXT: .long 30 # Field reloc section string offset=30
; CHECK-NEXT: .long 8
; CHECK-NEXT: .long .Ltmp{{[0-9]+}}
; CHECK-NEXT: .long 2
; CHECK-NEXT: .long 36
; CHECK-NEXT: .long 1
; CHECK-NEXT: .long .Ltmp{{[0-9]+}}
; CHECK-NEXT: .long 2
; CHECK-NEXT: .long 36
; CHECK-NEXT: .long 0
; CHECK-NEXT: .long .Ltmp{{[0-9]+}}
; CHECK-NEXT: .long 2
; CHECK-NEXT: .long 36
; CHECK-NEXT: .long 0
; CHECK-NEXT: .long .Ltmp{{[0-9]+}}
; CHECK-NEXT: .long 2
; CHECK-NEXT: .long 36
; CHECK-NEXT: .long 0
; CHECK-NEXT: .long .Ltmp{{[0-9]+}}
; CHECK-NEXT: .long 2
; CHECK-NEXT: .long 36
; CHECK-NEXT: .long 4
; CHECK-NEXT: .long .Ltmp{{[0-9]+}}
; CHECK-NEXT: .long 2
; CHECK-NEXT: .long 36
; CHECK-NEXT: .long 5
; CHECK-NEXT: .long .Ltmp{{[0-9]+}}
; CHECK-NEXT: .long 2
; CHECK-NEXT: .long 36
; CHECK-NEXT: .long 5
; CHECK-NEXT: .long .Ltmp{{[0-9]+}}
; CHECK-NEXT: .long 2
; CHECK-NEXT: .long 36
; CHECK-NEXT: .long 3
; Function Attrs: nounwind readnone
declare i16* @llvm.preserve.struct.access.index.p0i16.p0s_struct.ss(%struct.s*, i32, i32) #1
; Function Attrs: nounwind readnone
declare i32 @llvm.bpf.preserve.field.info.p0i16(i16*, i64) #1
; Function Attrs: nounwind readnone speculatable willreturn
declare void @llvm.dbg.value(metadata, metadata, metadata) #2
attributes #0 = { nounwind readonly "correctly-rounded-divide-sqrt-fp-math"="false" "disable-tail-calls"="false" "frame-pointer"="all" "less-precise-fpmad"="false" "min-legal-vector-width"="0" "no-infs-fp-math"="false" "no-jump-tables"="false" "no-nans-fp-math"="false" "no-signed-zeros-fp-math"="false" "no-trapping-math"="false" "stack-protector-buffer-size"="8" "unsafe-fp-math"="false" "use-soft-float"="false" }
attributes #1 = { nounwind readnone }
attributes #2 = { nounwind readnone speculatable willreturn }
!llvm.dbg.cu = !{!0}
!llvm.module.flags = !{!22, !23, !24}
!llvm.ident = !{!25}
!0 = distinct !DICompileUnit(language: DW_LANG_C99, file: !1, producer: "clang version 10.0.0 (https://github.com/llvm/llvm-project.git 923aa0ce806f7739b754167239fee2c9a15e2f31)", isOptimized: true, runtimeVersion: 0, emissionKind: FullDebug, enums: !2, retainedTypes: !12, nameTableKind: None)
!1 = !DIFile(filename: "test.c", directory: "/tmp/home/yhs/work/tests/core")
!2 = !{!3}
!3 = !DICompositeType(tag: DW_TAG_enumeration_type, file: !1, line: 6, baseType: !4, size: 32, elements: !5)
!4 = !DIBasicType(name: "unsigned int", size: 32, encoding: DW_ATE_unsigned)
!5 = !{!6, !7, !8, !9, !10, !11}
!6 = !DIEnumerator(name: "FIELD_BYTE_OFFSET", value: 0, isUnsigned: true)
!7 = !DIEnumerator(name: "FIELD_BYTE_SIZE", value: 1, isUnsigned: true)
!8 = !DIEnumerator(name: "FIELD_EXISTENCE", value: 2, isUnsigned: true)
!9 = !DIEnumerator(name: "FIELD_SIGNEDNESS", value: 3, isUnsigned: true)
!10 = !DIEnumerator(name: "FIELD_LSHIFT_U64", value: 4, isUnsigned: true)
!11 = !DIEnumerator(name: "FIELD_RSHIFT_U64", value: 5, isUnsigned: true)
!12 = !{!13, !15, !16, !18, !19, !21}
!13 = !DIDerivedType(tag: DW_TAG_pointer_type, baseType: !14, size: 64)
!14 = !DIBasicType(name: "unsigned char", size: 8, encoding: DW_ATE_unsigned_char)
!15 = !DIDerivedType(tag: DW_TAG_pointer_type, baseType: null, size: 64)
!16 = !DIDerivedType(tag: DW_TAG_pointer_type, baseType: !17, size: 64)
!17 = !DIBasicType(name: "unsigned short", size: 16, encoding: DW_ATE_unsigned)
!18 = !DIDerivedType(tag: DW_TAG_pointer_type, baseType: !4, size: 64)
!19 = !DIDerivedType(tag: DW_TAG_pointer_type, baseType: !20, size: 64)
!20 = !DIBasicType(name: "long long unsigned int", size: 64, encoding: DW_ATE_unsigned)
!21 = !DIBasicType(name: "long long int", size: 64, encoding: DW_ATE_signed)
!22 = !{i32 2, !"Dwarf Version", i32 4}
!23 = !{i32 2, !"Debug Info Version", i32 3}
!24 = !{i32 1, !"wchar_size", i32 4}
!25 = !{!"clang version 10.0.0 (https://github.com/llvm/llvm-project.git 923aa0ce806f7739b754167239fee2c9a15e2f31)"}
!26 = distinct !DISubprogram(name: "field_read", scope: !1, file: !1, line: 14, type: !27, scopeLine: 14, flags: DIFlagPrototyped, isDefinition: true, isOptimized: true, unit: !0, retainedNodes: !36)
!27 = !DISubroutineType(types: !28)
!28 = !{!29, !30}
!29 = !DIBasicType(name: "int", size: 32, encoding: DW_ATE_signed)
!30 = !DIDerivedType(tag: DW_TAG_pointer_type, baseType: !31, size: 64)
!31 = distinct !DICompositeType(tag: DW_TAG_structure_type, name: "s", file: !1, line: 1, size: 64, elements: !32)
!32 = !{!33, !34, !35}
!33 = !DIDerivedType(tag: DW_TAG_member, name: "a", scope: !31, file: !1, line: 2, baseType: !29, size: 32)
!34 = !DIDerivedType(tag: DW_TAG_member, name: "b1", scope: !31, file: !1, line: 3, baseType: !29, size: 9, offset: 32, flags: DIFlagBitField, extraData: i64 32)
!35 = !DIDerivedType(tag: DW_TAG_member, name: "b2", scope: !31, file: !1, line: 4, baseType: !29, size: 4, offset: 41, flags: DIFlagBitField, extraData: i64 32)
!36 = !{!37, !38, !39, !40}
!37 = !DILocalVariable(name: "arg", arg: 1, scope: !26, file: !1, line: 14, type: !30)
!38 = !DILocalVariable(name: "ull", scope: !26, file: !1, line: 15, type: !20)
!39 = !DILocalVariable(name: "offset", scope: !26, file: !1, line: 16, type: !4)
!40 = !DILocalVariable(name: "size", scope: !26, file: !1, line: 17, type: !4)
!41 = !DILocation(line: 0, scope: !26)
!42 = !DILocation(line: 16, column: 56, scope: !26)
!43 = !DILocation(line: 16, column: 21, scope: !26)
!44 = !DILocation(line: 17, column: 19, scope: !26)
!45 = !DILocation(line: 18, column: 3, scope: !26)
!46 = !DILocation(line: 20, column: 30, scope: !47)
!47 = distinct !DILexicalBlock(scope: !26, file: !1, line: 18, column: 16)
!48 = !DILocation(line: 20, column: 42, scope: !47)
!49 = !DILocation(line: 20, column: 11, scope: !47)
!50 = !{!51, !51, i64 0}
!51 = !{!"omnipotent char", !52, i64 0}
!52 = !{!"Simple C/C++ TBAA"}
!53 = !DILocation(line: 20, column: 53, scope: !47)
!54 = !DILocation(line: 22, column: 31, scope: !47)
!55 = !DILocation(line: 22, column: 43, scope: !47)
!56 = !DILocation(line: 22, column: 12, scope: !47)
!57 = !DILocation(line: 22, column: 11, scope: !47)
!58 = !{!59, !59, i64 0}
!59 = !{!"short", !51, i64 0}
!60 = !DILocation(line: 22, column: 54, scope: !47)
!61 = !DILocation(line: 24, column: 29, scope: !47)
!62 = !DILocation(line: 24, column: 41, scope: !47)
!63 = !DILocation(line: 24, column: 12, scope: !47)
!64 = !DILocation(line: 24, column: 11, scope: !47)
!65 = !{!66, !66, i64 0}
!66 = !{!"int", !51, i64 0}
!67 = !DILocation(line: 24, column: 52, scope: !47)
!68 = !DILocation(line: 26, column: 35, scope: !47)
!69 = !DILocation(line: 26, column: 47, scope: !47)
!70 = !DILocation(line: 26, column: 12, scope: !47)
!71 = !DILocation(line: 26, column: 11, scope: !47)
!72 = !{!73, !73, i64 0}
!73 = !{!"long long", !51, i64 0}
!74 = !DILocation(line: 26, column: 58, scope: !47)
!75 = !DILocation(line: 28, column: 11, scope: !26)
!76 = !DILocation(line: 28, column: 7, scope: !26)
!77 = !DILocation(line: 29, column: 7, scope: !78)
!78 = distinct !DILexicalBlock(scope: !26, file: !1, line: 29, column: 7)
!79 = !DILocation(line: 29, column: 7, scope: !26)
!80 = !DILocation(line: 32, column: 1, scope: !26)
|
