diff options
Diffstat (limited to 'clang')
17 files changed, 359 insertions, 1 deletions
diff --git a/clang/include/clang/Basic/DiagnosticFrontendKinds.td b/clang/include/clang/Basic/DiagnosticFrontendKinds.td index 7a990164b0d..3ab18913a45 100644 --- a/clang/include/clang/Basic/DiagnosticFrontendKinds.td +++ b/clang/include/clang/Basic/DiagnosticFrontendKinds.td @@ -275,7 +275,12 @@ def warn_profile_data_missing : Warning< def warn_profile_data_unprofiled : Warning< "no profile data available for file \"%0\"">, InGroup<ProfileInstrUnprofiled>; - +def warn_profile_data_misexpect : Warning< + "Potential performance regression from use of __builtin_expect(): " + "Annotation was correct on %0 of profiled executions.">, + BackendInfo, + InGroup<MisExpect>, + DefaultIgnore; } // end of instrumentation issue category } diff --git a/clang/include/clang/Basic/DiagnosticGroups.td b/clang/include/clang/Basic/DiagnosticGroups.td index ee6ecb9a445..a74427dba2d 100644 --- a/clang/include/clang/Basic/DiagnosticGroups.td +++ b/clang/include/clang/Basic/DiagnosticGroups.td @@ -1042,6 +1042,7 @@ def BackendOptimizationFailure : DiagGroup<"pass-failed">; def ProfileInstrMissing : DiagGroup<"profile-instr-missing">; def ProfileInstrOutOfDate : DiagGroup<"profile-instr-out-of-date">; def ProfileInstrUnprofiled : DiagGroup<"profile-instr-unprofiled">; +def MisExpect : DiagGroup<"misexpect">; // AddressSanitizer frontend instrumentation remarks. def SanitizeAddressRemarks : DiagGroup<"sanitize-address">; diff --git a/clang/lib/CodeGen/CodeGenAction.cpp b/clang/lib/CodeGen/CodeGenAction.cpp index 2356f84c05d..87bda4a0fc2 100644 --- a/clang/lib/CodeGen/CodeGenAction.cpp +++ b/clang/lib/CodeGen/CodeGenAction.cpp @@ -14,6 +14,7 @@ #include "clang/AST/ASTContext.h" #include "clang/AST/DeclCXX.h" #include "clang/AST/DeclGroup.h" +#include "clang/Basic/DiagnosticFrontend.h" #include "clang/Basic/FileManager.h" #include "clang/Basic/LangStandard.h" #include "clang/Basic/SourceManager.h" @@ -365,6 +366,9 @@ namespace clang { bool StackSizeDiagHandler(const llvm::DiagnosticInfoStackSize &D); /// Specialized handler for unsupported backend feature diagnostic. void UnsupportedDiagHandler(const llvm::DiagnosticInfoUnsupported &D); + /// Specialized handler for misexpect warnings. + /// Note that misexpect remarks are emitted through ORE + void MisExpectDiagHandler(const llvm::DiagnosticInfoMisExpect &D); /// Specialized handlers for optimization remarks. /// Note that these handlers only accept remarks and they always handle /// them. @@ -617,6 +621,25 @@ void BackendConsumer::UnsupportedDiagHandler( << Filename << Line << Column; } +void BackendConsumer::MisExpectDiagHandler( + const llvm::DiagnosticInfoMisExpect &D) { + StringRef Filename; + unsigned Line, Column; + bool BadDebugInfo = false; + FullSourceLoc Loc = + getBestLocationFromDebugLoc(D, BadDebugInfo, Filename, Line, Column); + + Diags.Report(Loc, diag::warn_profile_data_misexpect) << D.getMsg().str(); + + if (BadDebugInfo) + // If we were not able to translate the file:line:col information + // back to a SourceLocation, at least emit a note stating that + // we could not translate this location. This can happen in the + // case of #line directives. + Diags.Report(Loc, diag::note_fe_backend_invalid_loc) + << Filename << Line << Column; +} + void BackendConsumer::EmitOptimizationMessage( const llvm::DiagnosticInfoOptimizationBase &D, unsigned DiagID) { // We only support warnings and remarks. @@ -787,6 +810,9 @@ void BackendConsumer::DiagnosticHandlerImpl(const DiagnosticInfo &DI) { case llvm::DK_Unsupported: UnsupportedDiagHandler(cast<DiagnosticInfoUnsupported>(DI)); return; + case llvm::DK_MisExpect: + MisExpectDiagHandler(cast<DiagnosticInfoMisExpect>(DI)); + return; default: // Plugin IDs are not bound to any value as they are set dynamically. ComputeDiagRemarkID(Severity, backend_plugin, DiagID); diff --git a/clang/lib/Frontend/CompilerInvocation.cpp b/clang/lib/Frontend/CompilerInvocation.cpp index 99713e5e162..38d5694e7cd 100644 --- a/clang/lib/Frontend/CompilerInvocation.cpp +++ b/clang/lib/Frontend/CompilerInvocation.cpp @@ -3453,6 +3453,9 @@ bool CompilerInvocation::CreateFromArgs(CompilerInvocation &Res, } } + if (Diags.isIgnored(diag::warn_profile_data_misexpect, SourceLocation())) + Res.FrontendOpts.LLVMArgs.push_back("-pgo-warn-misexpect"); + LangOpts.FunctionAlignment = getLastArgIntValue(Args, OPT_function_alignment, 0, Diags); diff --git a/clang/test/Profile/Inputs/misexpect-branch-nonconst-expect-arg.proftext b/clang/test/Profile/Inputs/misexpect-branch-nonconst-expect-arg.proftext new file mode 100644 index 00000000000..a99351c06e5 --- /dev/null +++ b/clang/test/Profile/Inputs/misexpect-branch-nonconst-expect-arg.proftext @@ -0,0 +1,9 @@ +bar +# Func Hash: +11262309464 +# Num Counters: +2 +# Counter Values: +200000 +2 + diff --git a/clang/test/Profile/Inputs/misexpect-branch.proftext b/clang/test/Profile/Inputs/misexpect-branch.proftext new file mode 100644 index 00000000000..b809c1491fb --- /dev/null +++ b/clang/test/Profile/Inputs/misexpect-branch.proftext @@ -0,0 +1,9 @@ +bar +# Func Hash: +45795613684824 +# Num Counters: +2 +# Counter Values: +200000 +0 + diff --git a/clang/test/Profile/Inputs/misexpect-switch-default-only.proftext b/clang/test/Profile/Inputs/misexpect-switch-default-only.proftext new file mode 100644 index 00000000000..ac59378e768 --- /dev/null +++ b/clang/test/Profile/Inputs/misexpect-switch-default-only.proftext @@ -0,0 +1,12 @@ +main +# Func Hash: +79676873694057560 +# Num Counters: +5 +# Counter Values: +1 +20 +20000 +20000 +20000 + diff --git a/clang/test/Profile/Inputs/misexpect-switch-default.proftext b/clang/test/Profile/Inputs/misexpect-switch-default.proftext new file mode 100644 index 00000000000..7b2d59781a1 --- /dev/null +++ b/clang/test/Profile/Inputs/misexpect-switch-default.proftext @@ -0,0 +1,16 @@ +main +# Func Hash: +8712453512413296413 +# Num Counters: +9 +# Counter Values: +1 +20000 +20000 +4066 +11889 +0 +0 +4045 +0 + diff --git a/clang/test/Profile/Inputs/misexpect-switch.proftext b/clang/test/Profile/Inputs/misexpect-switch.proftext new file mode 100644 index 00000000000..ce4c96b3e3a --- /dev/null +++ b/clang/test/Profile/Inputs/misexpect-switch.proftext @@ -0,0 +1,16 @@ +main +# Func Hash: +1965403898329309329 +# Num Counters: +9 +# Counter Values: +1 +20 +20000 +20000 +12 +26 +0 +0 +19962 + diff --git a/clang/test/Profile/misexpect-branch-cold.c b/clang/test/Profile/misexpect-branch-cold.c new file mode 100644 index 00000000000..6d34f92a254 --- /dev/null +++ b/clang/test/Profile/misexpect-branch-cold.c @@ -0,0 +1,26 @@ +// Test that misexpect emits no warning when prediction is correct + +// RUN: llvm-profdata merge %S/Inputs/misexpect-branch.proftext -o %t.profdata +// RUN: %clang_cc1 %s -O2 -o - -disable-llvm-passes -emit-llvm -fprofile-instrument-use-path=%t.profdata -verify -Wmisexpect + +// expected-no-diagnostics +#define likely(x) __builtin_expect(!!(x), 1) +#define unlikely(x) __builtin_expect(!!(x), 0) + +int foo(int); +int baz(int); +int buzz(); + +const int inner_loop = 100; +const int outer_loop = 2000; + +int bar() { + int rando = buzz(); + int x = 0; + if (unlikely(rando % (outer_loop * inner_loop) == 0)) { + x = baz(rando); + } else { + x = foo(50); + } + return x; +} diff --git a/clang/test/Profile/misexpect-branch-nonconst-expected-val.c b/clang/test/Profile/misexpect-branch-nonconst-expected-val.c new file mode 100644 index 00000000000..c5167b9a2a0 --- /dev/null +++ b/clang/test/Profile/misexpect-branch-nonconst-expected-val.c @@ -0,0 +1,23 @@ +// Test that misexpect emits no warning when condition is not a compile-time constant + +// RUN: llvm-profdata merge %S/Inputs/misexpect-branch-nonconst-expect-arg.proftext -o %t.profdata +// RUN: %clang_cc1 %s -O2 -o - -disable-llvm-passes -emit-llvm -fprofile-instrument-use-path=%t.profdata -verify -Wmisexpect + +// expected-no-diagnostics +int foo(int); +int baz(int); +int buzz(); + +const int inner_loop = 100; +const int outer_loop = 2000; + +int bar() { + int rando = buzz(); + int x = 0; + if (__builtin_expect(rando % (outer_loop * inner_loop) == 0, buzz())) { + x = baz(rando); + } else { + x = foo(50); + } + return x; +} diff --git a/clang/test/Profile/misexpect-branch-unpredictable.c b/clang/test/Profile/misexpect-branch-unpredictable.c new file mode 100644 index 00000000000..6c4f90146a2 --- /dev/null +++ b/clang/test/Profile/misexpect-branch-unpredictable.c @@ -0,0 +1,25 @@ +// Test that misexpect emits no warning when prediction is correct + +// RUN: llvm-profdata merge %S/Inputs/misexpect-branch.proftext -o %t.profdata +// RUN: %clang_cc1 %s -O2 -o - -disable-llvm-passes -emit-llvm -fprofile-instrument-use-path=%t.profdata -verify -Wmisexpect + +// expected-no-diagnostics +#define unpredictable(x) __builtin_unpredictable(!!(x)) + +int foo(int); +int baz(int); +int buzz(); + +const int inner_loop = 100; +const int outer_loop = 2000; + +int bar() { + int rando = buzz(); + int x = 0; + if (unpredictable(rando % (outer_loop * inner_loop) == 0)) { + x = baz(rando); + } else { + x = foo(50); + } + return x; +} diff --git a/clang/test/Profile/misexpect-branch.c b/clang/test/Profile/misexpect-branch.c new file mode 100644 index 00000000000..503aa7398e9 --- /dev/null +++ b/clang/test/Profile/misexpect-branch.c @@ -0,0 +1,28 @@ +// Test that misexpect detects mis-annotated branches + +// RUN: llvm-profdata merge %S/Inputs/misexpect-branch.proftext -o %t.profdata +// RUN: %clang_cc1 %s -O2 -o - -emit-llvm -fprofile-instrument-use-path=%t.profdata -verify=imprecise -Wmisexpect +// RUN: %clang_cc1 %s -O2 -o - -emit-llvm -fprofile-instrument-use-path=%t.profdata -verify=exact -Wmisexpect -debug-info-kind=line-tables-only +// RUN: %clang_cc1 %s -O2 -o - -disable-llvm-passes -emit-llvm -fprofile-instrument-use-path=%t.profdata -verify=foo + +// foo-no-diagnostics +#define likely(x) __builtin_expect(!!(x), 1) +#define unlikely(x) __builtin_expect(!!(x), 0) + +int foo(int); +int baz(int); +int buzz(); + +const int inner_loop = 100; +const int outer_loop = 2000; + +int bar() { // imprecise-warning-re {{Potential performance regression from use of __builtin_expect(): Annotation was correct on {{.+}}% ({{[0-9]+ / [0-9]+}}) of profiled executions.}} + int rando = buzz(); + int x = 0; + if (likely(rando % (outer_loop * inner_loop) == 0)) { // exact-warning-re {{Potential performance regression from use of __builtin_expect(): Annotation was correct on {{.+}}% ({{[0-9]+ / [0-9]+}}) of profiled executions.}} + x = baz(rando); + } else { + x = foo(50); + } + return x; +} diff --git a/clang/test/Profile/misexpect-switch-default.c b/clang/test/Profile/misexpect-switch-default.c new file mode 100644 index 00000000000..3d1079d79f9 --- /dev/null +++ b/clang/test/Profile/misexpect-switch-default.c @@ -0,0 +1,40 @@ +// Test that misexpect detects mis-annotated switch statements for default case + +// RUN: llvm-profdata merge %S/Inputs/misexpect-switch-default.proftext -o %t.profdata +// RUN: %clang_cc1 %s -O2 -o - -emit-llvm -fprofile-instrument-use-path=%t.profdata -verify -Wmisexpect -debug-info-kind=line-tables-only + +int sum(int *buff, int size); +int random_sample(int *buff, int size); +int rand(); +void init_arry(); + +const int inner_loop = 1000; +const int outer_loop = 20; +const int arry_size = 25; + +int arry[arry_size] = {0}; + +int main() { + init_arry(); + int val = 0; + int j; + for (j = 0; j < outer_loop * inner_loop; ++j) { + unsigned condition = rand() % 5; + switch (__builtin_expect(condition, 6)) { // expected-warning-re {{Potential performance regression from use of __builtin_expect(): Annotation was correct on {{.+}}% ({{[0-9]+ / [0-9]+}}) of profiled executions.}} + case 0: + val += sum(arry, arry_size); + break; + case 1: + case 2: + case 3: + break; + case 4: + val += random_sample(arry, arry_size); + break; + default: + __builtin_unreachable(); + } // end switch + } // end outer_loop + + return 0; +} diff --git a/clang/test/Profile/misexpect-switch-nonconst.c b/clang/test/Profile/misexpect-switch-nonconst.c new file mode 100644 index 00000000000..bf2143b6f43 --- /dev/null +++ b/clang/test/Profile/misexpect-switch-nonconst.c @@ -0,0 +1,43 @@ +// Test that misexpect emits no warning when switch condition is non-const + +// RUN: llvm-profdata merge %S/Inputs/misexpect-switch.proftext -o %t.profdata +// RUN: %clang_cc1 %s -O2 -o - -disable-llvm-passes -emit-llvm -fprofile-instrument-use-path=%t.profdata -verify -Wmisexpect + +// expected-no-diagnostics +int sum(int *buff, int size); +int random_sample(int *buff, int size); +int rand(); +void init_arry(); + +const int inner_loop = 1000; +const int outer_loop = 20; +const int arry_size = 25; + +int arry[arry_size] = {0}; + +int main() { + init_arry(); + int val = 0; + + int j, k; + for (j = 0; j < outer_loop; ++j) { + for (k = 0; k < inner_loop; ++k) { + unsigned condition = rand() % 10000; + switch (__builtin_expect(condition, rand())) { + case 0: + val += sum(arry, arry_size); + break; + case 1: + case 2: + case 3: + case 4: + val += random_sample(arry, arry_size); + break; + default: + __builtin_unreachable(); + } // end switch + } // end inner_loop + } // end outer_loop + + return 0; +} diff --git a/clang/test/Profile/misexpect-switch-only-default-case.c b/clang/test/Profile/misexpect-switch-only-default-case.c new file mode 100644 index 00000000000..3886472e2b4 --- /dev/null +++ b/clang/test/Profile/misexpect-switch-only-default-case.c @@ -0,0 +1,35 @@ +// Test that misexpect emits no warning when there is only one switch case + +// RUN: llvm-profdata merge %S/Inputs/misexpect-switch-default-only.proftext -o %t.profdata +// RUN: %clang_cc1 %s -O2 -o - -emit-llvm -fprofile-instrument-use-path=%t.profdata -verify -Wmisexpect -debug-info-kind=line-tables-only + +// expected-no-diagnostics +int sum(int *buff, int size); +int random_sample(int *buff, int size); +int rand(); +void init_arry(); + +const int inner_loop = 1000; +const int outer_loop = 20; +const int arry_size = 25; + +int arry[arry_size] = {0}; + +int main() { + init_arry(); + int val = 0; + + int j, k; + for (j = 0; j < outer_loop; ++j) { + for (k = 0; k < inner_loop; ++k) { + unsigned condition = rand() % 10000; + switch (__builtin_expect(condition, 0)) { + default: + val += random_sample(arry, arry_size); + break; + }; // end switch + } // end inner_loop + } // end outer_loop + + return 0; +} diff --git a/clang/test/Profile/misexpect-switch.c b/clang/test/Profile/misexpect-switch.c new file mode 100644 index 00000000000..a7f01bcc998 --- /dev/null +++ b/clang/test/Profile/misexpect-switch.c @@ -0,0 +1,41 @@ +// Test that misexpect detects mis-annotated switch statements + +// RUN: llvm-profdata merge %S/Inputs/misexpect-switch.proftext -o %t.profdata +// RUN: %clang_cc1 %s -O2 -o - -emit-llvm -fprofile-instrument-use-path=%t.profdata -verify -Wmisexpect -debug-info-kind=line-tables-only + +int sum(int *buff, int size); +int random_sample(int *buff, int size); +int rand(); +void init_arry(); + +const int inner_loop = 1000; +const int outer_loop = 20; +const int arry_size = 25; + +int arry[arry_size] = {0}; + +int main() { + init_arry(); + int val = 0; + + int j, k; + for (j = 0; j < outer_loop; ++j) { + for (k = 0; k < inner_loop; ++k) { + unsigned condition = rand() % 10000; + switch (__builtin_expect(condition, 0)) { // expected-warning-re {{Potential performance regression from use of __builtin_expect(): Annotation was correct on {{.+}}% ({{[0-9]+ / [0-9]+}}) of profiled executions.}} + case 0: + val += sum(arry, arry_size); + break; + case 1: + case 2: + case 3: + break; + default: + val += random_sample(arry, arry_size); + break; + } // end switch + } // end inner_loop + } // end outer_loop + + return 0; +} |
