[gcov] Improve tests and lower the minimum supported version to gcov 3.4

global-ctor.ll no longer checks what it intended to check
(@_GLOBAL__sub_I_global-ctor.ll needs a !dbg to work).
Rewrite it.

gcov 3.4 and gcov 4.2 use the same format, thus we can lower the version
requirement to 3.4
This commit is contained in:
Fangrui Song 2020-06-06 23:11:31 -07:00
parent c36c2475a2
commit a7a8160485
3 changed files with 38 additions and 56 deletions

View File

@ -42,7 +42,7 @@ class FileInfo;
namespace GCOV {
enum GCOVVersion { V402, V407, V408, V800, V900 };
enum GCOVVersion { V304, V407, V408, V800, V900 };
/// A struct for passing gcov options between functions.
struct Options {
@ -132,8 +132,8 @@ public:
// r173147: split checksum into cfg checksum and line checksum.
Version = GCOV::V407;
return true;
} else {
Version = GCOV::V402;
} else if (Major == 4 || (Major == 3 && Minor >= 4)) {
Version = GCOV::V304;
return true;
}
errs() << "unexpected version: " << str << "\n";

View File

@ -179,14 +179,13 @@ bool GCOVFile::readGCDA(GCOVBuffer &buf) {
if (length == 0) // Placeholder
continue;
// As of GCC 10, GCOV_TAG_FUNCTION_LENGTH has never been larger than 3.
if (length != 3 || !buf.readInt(ident))
if ((length != 2 && length != 3) || !buf.readInt(ident))
return false;
auto It = IdentToFunction.find(ident);
uint32_t linenoChecksum, cfgChecksum;
uint32_t linenoChecksum, cfgChecksum = 0;
buf.readInt(linenoChecksum);
buf.readInt(cfgChecksum);
if (Version < GCOV::V407)
cfgChecksum = 0;
if (Version >= GCOV::V407)
buf.readInt(cfgChecksum);
if (It != IdentToFunction.end()) {
fn = It->second;
if (linenoChecksum != fn->linenoChecksum ||

View File

@ -1,60 +1,43 @@
; RUN: rm -rf %t && mkdir -p %t
; RUN: echo '!16 = !{!"%/t/global-ctor.ll", !0}' > %t/1
; RUN: cat %s %t/1 > %t/2
; RUN: opt -insert-gcov-profiling -disable-output < %t/2
; RUN: not grep '_GLOBAL__sub_I_global-ctor' %t/global-ctor.gcno
; RUN: rm %t/global-ctor.gcno
;; For a global constructor, _GLOBAL__sub_I_ only has artificial lines.
;; Test that we don't instrument those functions.
; RUN: opt -S -insert-gcov-profiling < %s | FileCheck %s
; RUN: opt -S -passes=insert-gcov-profiling < %s | FileCheck %s
; RUN: opt -passes=insert-gcov-profiling -disable-output < %t/2
; RUN: not grep '_GLOBAL__sub_I_global-ctor' %t/global-ctor.gcno
; RUN: rm %t/global-ctor.gcno
@var = dso_local global i32 0, align 4
@llvm.global_ctors = appending global [1 x { i32, void ()*, i8* }] [{ i32, void ()*, i8* } { i32 65535, void ()* @_GLOBAL__sub_I_a.cc, i8* null }]
@x = global i32 0, align 4
@llvm.global_ctors = appending global [1 x { i32, void ()*, i8* }] [{ i32, void ()*, i8* } { i32 65535, void ()* @_GLOBAL__sub_I_global-ctor.ll, i8* null }]
; Function Attrs: nounwind
define internal void @__cxx_global_var_init() #0 section ".text.startup" !dbg !4 {
define internal void @__cxx_global_var_init() section ".text.startup" !dbg !7 {
; CHECK: define internal void @__cxx_global_var_init()
; CHECK: @__llvm_gcov_ctr
; CHECK: call i32 @_Z3foov()
entry:
br label %0
; <label>:0 ; preds = %entry
%call = call i32 @_Z1fv(), !dbg !13
store i32 %call, i32* @x, align 4, !dbg !13
ret void, !dbg !13
%call = call i32 @_Z3foov(), !dbg !9
store i32 %call, i32* @var, align 4, !dbg !9
ret void, !dbg !9
}
declare i32 @_Z1fv() #1
declare i32 @_Z3foov()
; Function Attrs: nounwind
define internal void @_GLOBAL__sub_I_global-ctor.ll() #0 section ".text.startup" {
;; Artificial lines only. Don't instrument.
define internal void @_GLOBAL__sub_I_a.cc() section ".text.startup" !dbg !10 {
; CHECK: define internal void @_GLOBAL__sub_I_a.cc()
; CHECK-NOT: @__llvm_gcov_ctr
; CHECK: call void @__cxx_global_var_init()
entry:
br label %0
; <label>:0 ; preds = %entry
call void @__cxx_global_var_init(), !dbg !14
ret void, !dbg !14
call void @__cxx_global_var_init(), !dbg !11
ret void
}
attributes #0 = { nounwind }
attributes #1 = { "less-precise-fpmad"="false" "frame-pointer"="none" "no-infs-fp-math"="false" "no-nans-fp-math"="false" "no-realign-stack" "stack-protector-buffer-size"="8" "unsafe-fp-math"="false" "use-soft-float"="false" }
!llvm.dbg.cu = !{!0}
!llvm.module.flags = !{!10, !11}
!llvm.gcov = !{!16}
!llvm.ident = !{!12}
!llvm.module.flags = !{!3, !4}
!0 = distinct !DICompileUnit(language: DW_LANG_C_plus_plus, producer: "clang version 3.5.0 (trunk 210217)", isOptimized: false, emissionKind: LineTablesOnly, file: !1, enums: !2, retainedTypes: !2, globals: !2, imports: !2)
!1 = !DIFile(filename: "<stdin>", directory: "/home/nlewycky")
!0 = distinct !DICompileUnit(language: DW_LANG_C_plus_plus_14, file: !1, emissionKind: LineTablesOnly)
!1 = !DIFile(filename: "a.cc", directory: "/")
!2 = !{}
!4 = distinct !DISubprogram(name: "__cxx_global_var_init", line: 2, isLocal: true, isDefinition: true, virtualIndex: 6, flags: DIFlagPrototyped, isOptimized: false, unit: !0, scopeLine: 2, file: !5, scope: !6, type: !7, retainedNodes: !2)
!5 = !DIFile(filename: "global-ctor.ll", directory: "/home/nlewycky")
!6 = !DIFile(filename: "global-ctor.ll", directory: "/home/nlewycky")
!7 = !DISubroutineType(types: !2)
!8 = distinct !DISubprogram(name: "", linkageName: "_GLOBAL__sub_I_global-ctor.ll", isLocal: true, isDefinition: true, virtualIndex: 6, flags: DIFlagArtificial, isOptimized: false, unit: !0, file: !1, scope: !9, type: !7, retainedNodes: !2)
!9 = !DIFile(filename: "<stdin>", directory: "/home/nlewycky")
!10 = !{i32 2, !"Dwarf Version", i32 4}
!11 = !{i32 2, !"Debug Info Version", i32 3}
!12 = !{!"clang version 3.5.0 (trunk 210217)"}
!13 = !DILocation(line: 2, scope: !4)
!14 = !DILocation(line: 0, scope: !15)
!15 = !DILexicalBlockFile(discriminator: 0, file: !5, scope: !8)
!3 = !{i32 7, !"Dwarf Version", i32 4}
!4 = !{i32 2, !"Debug Info Version", i32 3}
!7 = distinct !DISubprogram(name: "__cxx_global_var_init", scope: !1, file: !1, line: 2, type: !8, scopeLine: 2, spFlags: DISPFlagLocalToUnit | DISPFlagDefinition, unit: !0, retainedNodes: !2)
!8 = !DISubroutineType(types: !2)
!9 = !DILocation(line: 2, column: 11, scope: !7)
!10 = distinct !DISubprogram(linkageName: "_GLOBAL__sub_I_a.cc", scope: !1, file: !1, type: !8, flags: DIFlagArtificial, spFlags: DISPFlagLocalToUnit | DISPFlagDefinition, unit: !0, retainedNodes: !2)
!11 = !DILocation(line: 0, scope: !10)