[llvm] 13d1592 - Reland A new option -print-on-crash that prints the IR as it was upon entering the last pass when there is a crash.
Jamie Schmeiser via llvm-commits
llvm-commits at lists.llvm.org
Thu Oct 7 12:02:55 PDT 2021
Author: Jamie Schmeiser
Date: 2021-10-07T15:02:19-04:00
New Revision: 13d1592716a65444314f501109ec9ca344ef1f87
URL: https://github.com/llvm/llvm-project/commit/13d1592716a65444314f501109ec9ca344ef1f87
DIFF: https://github.com/llvm/llvm-project/commit/13d1592716a65444314f501109ec9ca344ef1f87.diff
LOG: Reland A new option -print-on-crash that prints the IR as it was upon entering the last pass when there is a crash.
Summary:
The IR is saved in its print form before each pass is started and a
signal handler is registered. If the compilation crashes, the signal
handler will print the saved IR to dbgs(). This option
can be modified using -print-module-scope to get the IR for the complete
module. Filtering options can be used to improve performance by limiting
which passes (or functions) save the IR. Note that this option only works
with the new pass manager.
Author: Jamie Schmeiser <schmeise at ca.ibm.com>
Reviewed By: aeubanks (Arthur Eubanks) yrouban (Yevgeny Rouban)
Differential Revision: https://reviews.llvm.org/D86657
Added:
llvm/test/Other/print-on-crash.ll
Modified:
llvm/include/llvm/Passes/StandardInstrumentations.h
llvm/lib/Passes/PassBuilder.cpp
llvm/lib/Passes/PassRegistry.def
llvm/lib/Passes/StandardInstrumentations.cpp
Removed:
################################################################################
diff --git a/llvm/include/llvm/Passes/StandardInstrumentations.h b/llvm/include/llvm/Passes/StandardInstrumentations.h
index 2f573585e766d..6729ae5d484f1 100644
--- a/llvm/include/llvm/Passes/StandardInstrumentations.h
+++ b/llvm/include/llvm/Passes/StandardInstrumentations.h
@@ -187,17 +187,6 @@ template <typename IRUnitT> class ChangeReporter {
// Register required callbacks.
void registerRequiredCallbacks(PassInstrumentationCallbacks &PIC);
- // Return true when this is a defined function for which printing
- // of changes is desired.
- bool isInterestingFunction(const Function &F);
-
- // Return true when this is a pass for which printing of changes is desired.
- bool isInterestingPass(StringRef PassID);
-
- // Return true when this is a pass on IR for which printing
- // of changes is desired.
- bool isInteresting(Any IR, StringRef PassID);
-
// Called on the first IR processed.
virtual void handleInitialIR(Any IR) = 0;
// Called before and after a pass to get the representation of the IR.
@@ -409,6 +398,25 @@ class VerifyInstrumentation {
void registerCallbacks(PassInstrumentationCallbacks &PIC);
};
+// Print IR on crash.
+class PrintCrashIRInstrumentation {
+public:
+ PrintCrashIRInstrumentation()
+ : SavedIR("*** Dump of IR Before Last Pass Unknown ***") {}
+ ~PrintCrashIRInstrumentation();
+ void registerCallbacks(PassInstrumentationCallbacks &PIC);
+ void reportCrashIR();
+
+protected:
+ std::string SavedIR;
+
+private:
+ // The crash reporter that will report on a crash.
+ static PrintCrashIRInstrumentation *CrashReporter;
+ // Crash handler registered when print-on-crash is specified.
+ static void SignalHandler(void *);
+};
+
/// This class provides an interface to register all the standard pass
/// instrumentations and manages their state (if any).
class StandardInstrumentations {
@@ -421,6 +429,7 @@ class StandardInstrumentations {
IRChangedPrinter PrintChangedIR;
PseudoProbeVerifier PseudoProbeVerification;
InLineChangePrinter PrintChangedDiff;
+ PrintCrashIRInstrumentation PrintCrashIR;
VerifyInstrumentation Verify;
bool VerifyEach;
diff --git a/llvm/lib/Passes/PassBuilder.cpp b/llvm/lib/Passes/PassBuilder.cpp
index c3e7bc23ad23c..642453c143409 100644
--- a/llvm/lib/Passes/PassBuilder.cpp
+++ b/llvm/lib/Passes/PassBuilder.cpp
@@ -357,6 +357,13 @@ bool shouldPopulateClassToPassNames() {
!printAfterPasses().empty();
}
+// A pass for testing -print-on-crash.
+// DO NOT USE THIS EXCEPT FOR TESTING!
+class TriggerCrashPass : public PassInfoMixin<TriggerCrashPass> {
+public:
+ PreservedAnalyses run(Module &, ModuleAnalysisManager &) { assert(false); }
+};
+
} // namespace
PassBuilder::PassBuilder(TargetMachine *TM, PipelineTuningOptions PTO,
diff --git a/llvm/lib/Passes/PassRegistry.def b/llvm/lib/Passes/PassRegistry.def
index 655c472878a00..9f8c2cb11e04b 100644
--- a/llvm/lib/Passes/PassRegistry.def
+++ b/llvm/lib/Passes/PassRegistry.def
@@ -106,6 +106,7 @@ MODULE_PASS("strip-debug-declare", StripDebugDeclarePass())
MODULE_PASS("strip-nondebug", StripNonDebugSymbolsPass())
MODULE_PASS("strip-nonlinetable-debuginfo", StripNonLineTableDebugInfoPass())
MODULE_PASS("synthetic-counts-propagation", SyntheticCountsPropagation())
+MODULE_PASS("trigger-crash", TriggerCrashPass())
MODULE_PASS("verify", VerifierPass())
MODULE_PASS("wholeprogramdevirt", WholeProgramDevirtPass())
MODULE_PASS("dfsan", DataFlowSanitizerPass())
diff --git a/llvm/lib/Passes/StandardInstrumentations.cpp b/llvm/lib/Passes/StandardInstrumentations.cpp
index fbe4f25242c2d..9c374b8c5092a 100644
--- a/llvm/lib/Passes/StandardInstrumentations.cpp
+++ b/llvm/lib/Passes/StandardInstrumentations.cpp
@@ -27,10 +27,12 @@
#include "llvm/IR/PrintPasses.h"
#include "llvm/IR/Verifier.h"
#include "llvm/Support/CommandLine.h"
+#include "llvm/Support/CrashRecoveryContext.h"
#include "llvm/Support/Debug.h"
#include "llvm/Support/FormatVariadic.h"
#include "llvm/Support/MemoryBuffer.h"
#include "llvm/Support/Program.h"
+#include "llvm/Support/Signals.h"
#include "llvm/Support/raw_ostream.h"
#include <unordered_set>
#include <vector>
@@ -119,6 +121,12 @@ static cl::opt<std::string>
DiffBinary("print-changed-
diff -path", cl::Hidden, cl::init("
diff "),
cl::desc("system
diff used by change reporters"));
+// An option to print the IR that was being processed when a pass crashes.
+static cl::opt<bool>
+ PrintCrashIR("print-on-crash",
+ cl::desc("Print the last form of the IR before crash"),
+ cl::init(false), cl::Hidden);
+
namespace {
// Perform a system based
diff between \p Before and \p After, using
@@ -368,20 +376,11 @@ bool isIgnored(StringRef PassID) {
"DevirtSCCRepeatedPass", "ModuleInlinerWrapperPass"});
}
-} // namespace
-
-template <typename IRUnitT>
-ChangeReporter<IRUnitT>::~ChangeReporter<IRUnitT>() {
- assert(BeforeStack.empty() && "Problem with Change Printer stack.");
-}
-
-template <typename IRUnitT>
-bool ChangeReporter<IRUnitT>::isInterestingFunction(const Function &F) {
+bool isInterestingFunction(const Function &F) {
return isFunctionInPrintList(F.getName());
}
-template <typename IRUnitT>
-bool ChangeReporter<IRUnitT>::isInterestingPass(StringRef PassID) {
+bool isInterestingPass(StringRef PassID) {
if (isIgnored(PassID))
return false;
@@ -392,8 +391,7 @@ bool ChangeReporter<IRUnitT>::isInterestingPass(StringRef PassID) {
// Return true when this is a pass on IR for which printing
// of changes is desired.
-template <typename IRUnitT>
-bool ChangeReporter<IRUnitT>::isInteresting(Any IR, StringRef PassID) {
+bool isInteresting(Any IR, StringRef PassID) {
if (!isInterestingPass(PassID))
return false;
if (any_isa<const Function *>(IR))
@@ -401,6 +399,13 @@ bool ChangeReporter<IRUnitT>::isInteresting(Any IR, StringRef PassID) {
return true;
}
+} // namespace
+
+template <typename IRUnitT>
+ChangeReporter<IRUnitT>::~ChangeReporter<IRUnitT>() {
+ assert(BeforeStack.empty() && "Problem with Change Printer stack.");
+}
+
template <typename IRUnitT>
void ChangeReporter<IRUnitT>::saveIRBeforePass(Any IR, StringRef PassID) {
// Always need to place something on the stack because invalidated passes
@@ -1223,6 +1228,51 @@ StandardInstrumentations::StandardInstrumentations(
PrintChanged == ChangePrinter::PrintChangedColourDiffQuiet),
Verify(DebugLogging), VerifyEach(VerifyEach) {}
+PrintCrashIRInstrumentation *PrintCrashIRInstrumentation::CrashReporter =
+ nullptr;
+
+void PrintCrashIRInstrumentation::reportCrashIR() { dbgs() << SavedIR; }
+
+void PrintCrashIRInstrumentation::SignalHandler(void *) {
+ // Called by signal handlers so do not lock here
+ // Is the PrintCrashIRInstrumentation still alive?
+ if (!CrashReporter)
+ return;
+
+ assert(PrintCrashIR && "Did not expect to get here without option set.");
+ CrashReporter->reportCrashIR();
+}
+
+PrintCrashIRInstrumentation::~PrintCrashIRInstrumentation() {
+ if (!CrashReporter)
+ return;
+
+ assert(PrintCrashIR && "Did not expect to get here without option set.");
+ CrashReporter = nullptr;
+}
+
+void PrintCrashIRInstrumentation::registerCallbacks(
+ PassInstrumentationCallbacks &PIC) {
+ if (!PrintCrashIR || CrashReporter)
+ return;
+
+ sys::AddSignalHandler(SignalHandler, nullptr);
+ CrashReporter = this;
+
+ PIC.registerBeforeNonSkippedPassCallback([this](StringRef PassID, Any IR) {
+ SavedIR.clear();
+ raw_string_ostream OS(SavedIR);
+ OS << formatv("*** Dump of {0}IR Before Last Pass {1}",
+ llvm::forcePrintModuleIR() ? "Module " : "", PassID);
+ if (!isInteresting(IR, PassID)) {
+ OS << " Filtered Out ***\n";
+ return;
+ }
+ OS << " Started ***\n";
+ unwrapAndPrint(OS, IR);
+ });
+}
+
void StandardInstrumentations::registerCallbacks(
PassInstrumentationCallbacks &PIC, FunctionAnalysisManager *FAM) {
PrintIR.registerCallbacks(PIC);
@@ -1237,6 +1287,7 @@ void StandardInstrumentations::registerCallbacks(
if (VerifyEach)
Verify.registerCallbacks(PIC);
PrintChangedDiff.registerCallbacks(PIC);
+ PrintCrashIR.registerCallbacks(PIC);
}
namespace llvm {
diff --git a/llvm/test/Other/print-on-crash.ll b/llvm/test/Other/print-on-crash.ll
new file mode 100644
index 0000000000000..7e8ec2dc09ce6
--- /dev/null
+++ b/llvm/test/Other/print-on-crash.ll
@@ -0,0 +1,32 @@
+; A test that the hidden option -print-on-crash properly sets a signal handler
+; which gets called when a pass crashes. The trigger-crash pass asserts.
+
+; REQUIRES: asserts
+
+; RUN: not --crash opt -print-on-crash -passes=trigger-crash < %s 2>&1 | FileCheck %s --check-prefix=CHECK_SIMPLE
+
+; A test that the signal handler set by the hidden option -print-on-crash
+; is not called when no pass crashes.
+
+; RUN: opt -print-on-crash -passes="default<O2>" < %s 2>&1 | FileCheck %s --check-prefix=CHECK_NO_CRASH
+
+; RUN: not --crash opt -print-on-crash -print-module-scope -passes=trigger-crash < %s 2>&1 | FileCheck %s --check-prefix=CHECK_MODULE
+
+; RUN: not --crash opt -print-on-crash -print-module-scope -passes=trigger-crash -filter-passes="(anonymous namespace)::TriggerCrashPass" < %s 2>&1 | FileCheck %s --check-prefix=CHECK_MODULE
+
+; RUN: not --crash opt -print-on-crash -print-module-scope -passes=trigger-crash -filter-passes=blah < %s 2>&1 | FileCheck %s --check-prefix=CHECK_FILTERED
+
+; CHECK_SIMPLE: *** Dump of IR Before Last Pass {{.*}} Started ***
+; CHECK_SIMPLE: @main
+; CHECK_SIMPLE: entry:
+; CHECK_NO_CRASH-NOT: *** Dump of IR
+; CHECK_MODULE: *** Dump of Module IR Before Last Pass {{.*}} Started ***
+; CHECK_MODULE: ; ModuleID = {{.*}}
+; CHECK_FILTERED: *** Dump of Module IR Before Last Pass {{.*}} Filtered Out ***
+
+define i32 @main() {
+entry:
+ %retval = alloca i32, align 4
+ store i32 0, i32* %retval, align 4
+ ret i32 0
+}
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