[llvm] Add a pass to collect dropped var statistics for MIR (PR #126686)
Shubham Sandeep Rastogi via llvm-commits
llvm-commits at lists.llvm.org
Tue Feb 11 12:05:27 PST 2025
https://github.com/rastogishubham updated https://github.com/llvm/llvm-project/pull/126686
>From 5e59fa57d29e159f41957958ba541049f85652d6 Mon Sep 17 00:00:00 2001
From: Shubham Sandeep Rastogi <srastogi22 at apple.com>
Date: Mon, 10 Feb 2025 18:50:04 -0800
Subject: [PATCH 1/2] Move DroppedVariableStats code to lib/IR from lib/Passes.
Also Rewrite DroppedVariableStats to reduce .h file size
The DroppedVariableStats.h file include pulls in a lot of code and leads
to a significant compilation slowdown if included in
MachineFunctionPass.h, which is needed to enable dropped variable
statistics for MIR.
This patch moves all the code to a DroppedVariableStats.cpp file and
replaces those expensive includes with forward declarations to resolve
the issue.
---
.../{Passes => IR}/DroppedVariableStats.h | 146 ++++-------------
.../{Passes => IR}/DroppedVariableStatsIR.h | 50 +++---
.../llvm/Passes/StandardInstrumentations.h | 2 +-
llvm/lib/IR/CMakeLists.txt | 2 +
llvm/lib/IR/DroppedVariableStats.cpp | 147 ++++++++++++++++++
.../{Passes => IR}/DroppedVariableStatsIR.cpp | 40 ++++-
llvm/lib/Passes/CMakeLists.txt | 1 -
7 files changed, 235 insertions(+), 153 deletions(-)
rename llvm/include/llvm/{Passes => IR}/DroppedVariableStats.h (52%)
rename llvm/include/llvm/{Passes => IR}/DroppedVariableStatsIR.h (74%)
create mode 100644 llvm/lib/IR/DroppedVariableStats.cpp
rename llvm/lib/{Passes => IR}/DroppedVariableStatsIR.cpp (70%)
diff --git a/llvm/include/llvm/Passes/DroppedVariableStats.h b/llvm/include/llvm/IR/DroppedVariableStats.h
similarity index 52%
rename from llvm/include/llvm/Passes/DroppedVariableStats.h
rename to llvm/include/llvm/IR/DroppedVariableStats.h
index 30fbeae703b03..ebd74a69a8b91 100644
--- a/llvm/include/llvm/Passes/DroppedVariableStats.h
+++ b/llvm/include/llvm/IR/DroppedVariableStats.h
@@ -14,13 +14,19 @@
#ifndef LLVM_CODEGEN_DROPPEDVARIABLESTATS_H
#define LLVM_CODEGEN_DROPPEDVARIABLESTATS_H
-#include "llvm/IR/DebugInfoMetadata.h"
-#include "llvm/IR/DiagnosticInfo.h"
-#include "llvm/IR/Function.h"
-#include "llvm/IR/PassInstrumentation.h"
+#include "llvm/ADT/DenseSet.h"
+#include "llvm/ADT/SmallVector.h"
+#include <tuple>
namespace llvm {
+class DIScope;
+class DILocalVariable;
+class Function;
+class DILocation;
+class DebugLoc;
+class StringRef;
+
/// A unique key that represents a debug variable.
/// First const DIScope *: Represents the scope of the debug variable.
/// Second const DIScope *: Represents the InlinedAt scope of the debug
@@ -33,13 +39,7 @@ using VarID =
/// statistics.
class DroppedVariableStats {
public:
- DroppedVariableStats(bool DroppedVarStatsEnabled)
- : DroppedVariableStatsEnabled(DroppedVarStatsEnabled) {
- if (DroppedVarStatsEnabled)
- llvm::outs()
- << "Pass Level, Pass Name, Num of Dropped Variables, Func or "
- "Module Name\n";
- };
+ DroppedVariableStats(bool DroppedVarStatsEnabled);
virtual ~DroppedVariableStats() {}
@@ -50,20 +50,9 @@ class DroppedVariableStats {
bool getPassDroppedVariables() { return PassDroppedVariables; }
protected:
- void setup() {
- DebugVariablesStack.push_back(
- {DenseMap<const Function *, DebugVariables>()});
- InlinedAts.push_back(
- {DenseMap<StringRef, DenseMap<VarID, DILocation *>>()});
- }
-
- void cleanup() {
- assert(!DebugVariablesStack.empty() &&
- "DebugVariablesStack shouldn't be empty!");
- assert(!InlinedAts.empty() && "InlinedAts shouldn't be empty!");
- DebugVariablesStack.pop_back();
- InlinedAts.pop_back();
- }
+ void setup();
+
+ void cleanup();
bool DroppedVariableStatsEnabled = false;
struct DebugVariables {
@@ -73,7 +62,6 @@ class DroppedVariableStats {
DenseSet<VarID> DebugVariablesAfter;
};
-protected:
/// A stack of a DenseMap, that maps DebugVariables for every pass to an
/// llvm::Function. A stack is used because an optimization pass can call
/// other passes.
@@ -90,78 +78,27 @@ class DroppedVariableStats {
void calculateDroppedStatsAndPrint(DebugVariables &DbgVariables,
StringRef FuncName, StringRef PassID,
StringRef FuncOrModName,
- StringRef PassLevel,
- const Function *Func) {
- unsigned DroppedCount = 0;
- DenseSet<VarID> &DebugVariablesBeforeSet =
- DbgVariables.DebugVariablesBefore;
- DenseSet<VarID> &DebugVariablesAfterSet = DbgVariables.DebugVariablesAfter;
- auto It = InlinedAts.back().find(FuncName);
- if (It == InlinedAts.back().end())
- return;
- DenseMap<VarID, DILocation *> &InlinedAtsMap = It->second;
- // Find an Instruction that shares the same scope as the dropped #dbg_value
- // or has a scope that is the child of the scope of the #dbg_value, and has
- // an inlinedAt equal to the inlinedAt of the #dbg_value or it's inlinedAt
- // chain contains the inlinedAt of the #dbg_value, if such an Instruction is
- // found, debug information is dropped.
- for (VarID Var : DebugVariablesBeforeSet) {
- if (DebugVariablesAfterSet.contains(Var))
- continue;
- visitEveryInstruction(DroppedCount, InlinedAtsMap, Var);
- removeVarFromAllSets(Var, Func);
- }
- if (DroppedCount > 0) {
- llvm::outs() << PassLevel << ", " << PassID << ", " << DroppedCount
- << ", " << FuncOrModName << "\n";
- PassDroppedVariables = true;
- } else
- PassDroppedVariables = false;
- }
+ StringRef PassLevel, const Function *Func);
/// Check if a \p Var has been dropped or is a false positive. Also update the
/// \p DroppedCount if a debug variable is dropped.
bool updateDroppedCount(DILocation *DbgLoc, const DIScope *Scope,
const DIScope *DbgValScope,
DenseMap<VarID, DILocation *> &InlinedAtsMap,
- VarID Var, unsigned &DroppedCount) {
- // If the Scope is a child of, or equal to the DbgValScope and is inlined at
- // the Var's InlinedAt location, return true to signify that the Var has
- // been dropped.
- if (isScopeChildOfOrEqualTo(Scope, DbgValScope))
- if (isInlinedAtChildOfOrEqualTo(DbgLoc->getInlinedAt(),
- InlinedAtsMap[Var])) {
- // Found another instruction in the variable's scope, so there exists a
- // break point at which the variable could be observed. Count it as
- // dropped.
- DroppedCount++;
- return true;
- }
- return false;
- }
+ VarID Var, unsigned &DroppedCount);
+
/// Run code to populate relevant data structures over an llvm::Function or
/// llvm::MachineFunction.
- void run(DebugVariables &DbgVariables, StringRef FuncName, bool Before) {
- auto &VarIDSet = (Before ? DbgVariables.DebugVariablesBefore
- : DbgVariables.DebugVariablesAfter);
- auto &InlinedAtsMap = InlinedAts.back();
- if (Before)
- InlinedAtsMap.try_emplace(FuncName, DenseMap<VarID, DILocation *>());
- VarIDSet = DenseSet<VarID>();
- visitEveryDebugRecord(VarIDSet, InlinedAtsMap, FuncName, Before);
- }
+ void run(DebugVariables &DbgVariables, StringRef FuncName, bool Before);
+
/// Populate the VarIDSet and InlinedAtMap with the relevant information
/// needed for before and after pass analysis to determine dropped variable
/// status.
void populateVarIDSetAndInlinedMap(
const DILocalVariable *DbgVar, DebugLoc DbgLoc, DenseSet<VarID> &VarIDSet,
DenseMap<StringRef, DenseMap<VarID, DILocation *>> &InlinedAtsMap,
- StringRef FuncName, bool Before) {
- VarID Key{DbgVar->getScope(), DbgLoc->getInlinedAtScope(), DbgVar};
- VarIDSet.insert(Key);
- if (Before)
- InlinedAtsMap[FuncName].try_emplace(Key, DbgLoc.getInlinedAt());
- }
+ StringRef FuncName, bool Before);
+
/// Visit every llvm::Instruction or llvm::MachineInstruction and check if the
/// debug variable denoted by its ID \p Var may have been dropped by an
/// optimization pass.
@@ -179,47 +116,18 @@ class DroppedVariableStats {
private:
/// Remove a dropped debug variable's VarID from all Sets in the
/// DroppedVariablesBefore stack.
- void removeVarFromAllSets(VarID Var, const Function *F) {
- // Do not remove Var from the last element, it will be popped from the
- // stack.
- for (auto &DebugVariablesMap : llvm::drop_end(DebugVariablesStack))
- DebugVariablesMap[F].DebugVariablesBefore.erase(Var);
- }
+ void removeVarFromAllSets(VarID Var, const Function *F);
+
/// Return true if \p Scope is the same as \p DbgValScope or a child scope of
/// \p DbgValScope, return false otherwise.
bool isScopeChildOfOrEqualTo(const DIScope *Scope,
- const DIScope *DbgValScope) {
- while (Scope != nullptr) {
- if (VisitedScope.find(Scope) == VisitedScope.end()) {
- VisitedScope.insert(Scope);
- if (Scope == DbgValScope) {
- VisitedScope.clear();
- return true;
- }
- Scope = Scope->getScope();
- } else {
- VisitedScope.clear();
- return false;
- }
- }
- return false;
- }
+ const DIScope *DbgValScope);
+
/// Return true if \p InlinedAt is the same as \p DbgValInlinedAt or part of
/// the InlinedAt chain, return false otherwise.
bool isInlinedAtChildOfOrEqualTo(const DILocation *InlinedAt,
- const DILocation *DbgValInlinedAt) {
- if (DbgValInlinedAt == InlinedAt)
- return true;
- if (!DbgValInlinedAt)
- return false;
- auto *IA = InlinedAt;
- while (IA) {
- if (IA == DbgValInlinedAt)
- return true;
- IA = IA->getInlinedAt();
- }
- return false;
- }
+ const DILocation *DbgValInlinedAt);
+
bool PassDroppedVariables = false;
};
diff --git a/llvm/include/llvm/Passes/DroppedVariableStatsIR.h b/llvm/include/llvm/IR/DroppedVariableStatsIR.h
similarity index 74%
rename from llvm/include/llvm/Passes/DroppedVariableStatsIR.h
rename to llvm/include/llvm/IR/DroppedVariableStatsIR.h
index 18847b5c1ead8..72b91dbc7ed52 100644
--- a/llvm/include/llvm/Passes/DroppedVariableStatsIR.h
+++ b/llvm/include/llvm/IR/DroppedVariableStatsIR.h
@@ -14,12 +14,17 @@
#ifndef LLVM_CODEGEN_DROPPEDVARIABLESTATSIR_H
#define LLVM_CODEGEN_DROPPEDVARIABLESTATSIR_H
-#include "llvm/IR/InstIterator.h"
-#include "llvm/IR/Module.h"
-#include "llvm/Passes/DroppedVariableStats.h"
+#include "llvm/IR/DroppedVariableStats.h"
namespace llvm {
+class Any;
+class StringRef;
+class PassInstrumentationCallbacks;
+class Function;
+class Module;
+class DILocation;
+
/// A class to collect and print dropped debug information due to LLVM IR
/// optimization passes. After every LLVM IR pass is run, it will print how many
/// #dbg_values were dropped due to that pass.
@@ -28,56 +33,42 @@ class DroppedVariableStatsIR : public DroppedVariableStats {
DroppedVariableStatsIR(bool DroppedVarStatsEnabled)
: llvm::DroppedVariableStats(DroppedVarStatsEnabled) {}
- void runBeforePass(StringRef P, Any IR) {
- setup();
- if (const auto *M = unwrapIR<Module>(IR))
- return this->runOnModule(P, M, true);
- if (const auto *F = unwrapIR<Function>(IR))
- return this->runOnFunction(P, F, true);
- }
-
- void runAfterPass(StringRef P, Any IR) {
- if (const auto *M = unwrapIR<Module>(IR))
- runAfterPassModule(P, M);
- else if (const auto *F = unwrapIR<Function>(IR))
- runAfterPassFunction(P, F);
- cleanup();
- }
+ void runBeforePass(StringRef P, Any IR);
+
+ void runAfterPass(StringRef P, Any IR);
void registerCallbacks(PassInstrumentationCallbacks &PIC);
private:
const Function *Func;
- void runAfterPassFunction(StringRef PassID, const Function *F) {
- runOnFunction(PassID, F, false);
- calculateDroppedVarStatsOnFunction(F, PassID, F->getName().str(),
- "Function");
- }
+ void runAfterPassFunction(StringRef PassID, const Function *F);
+
+ void runAfterPassModule(StringRef PassID, const Module *M);
- void runAfterPassModule(StringRef PassID, const Module *M) {
- runOnModule(PassID, M, false);
- calculateDroppedVarStatsOnModule(M, PassID, M->getName().str(), "Module");
- }
/// Populate DebugVariablesBefore, DebugVariablesAfter, InlinedAts before or
/// after a pass has run to facilitate dropped variable calculation for an
/// llvm::Function.
void runOnFunction(StringRef PassID, const Function *F, bool Before);
+
/// Iterate over all Instructions in a Function and report any dropped debug
/// information.
void calculateDroppedVarStatsOnFunction(const Function *F, StringRef PassID,
StringRef FuncOrModName,
StringRef PassLevel);
+
/// Populate DebugVariablesBefore, DebugVariablesAfter, InlinedAts before or
/// after a pass has run to facilitate dropped variable calculation for an
/// llvm::Module. Calls runOnFunction on every Function in the Module.
void runOnModule(StringRef PassID, const Module *M, bool Before);
+
/// Iterate over all Functions in a Module and report any dropped debug
/// information. Will call calculateDroppedVarStatsOnFunction on every
/// Function.
void calculateDroppedVarStatsOnModule(const Module *M, StringRef PassID,
StringRef FuncOrModName,
StringRef PassLevel);
+
/// Override base class method to run on an llvm::Function specifically.
virtual void
visitEveryInstruction(unsigned &DroppedCount,
@@ -90,10 +81,7 @@ class DroppedVariableStatsIR : public DroppedVariableStats {
DenseMap<StringRef, DenseMap<VarID, DILocation *>> &InlinedAtsMap,
StringRef FuncName, bool Before) override;
- template <typename IRUnitT> static const IRUnitT *unwrapIR(Any IR) {
- const IRUnitT **IRPtr = llvm::any_cast<const IRUnitT *>(&IR);
- return IRPtr ? *IRPtr : nullptr;
- }
+ template <typename IRUnitT> static const IRUnitT *unwrapIR(Any IR);
};
} // namespace llvm
diff --git a/llvm/include/llvm/Passes/StandardInstrumentations.h b/llvm/include/llvm/Passes/StandardInstrumentations.h
index 4e62ee9c00daf..2af73cb714a76 100644
--- a/llvm/include/llvm/Passes/StandardInstrumentations.h
+++ b/llvm/include/llvm/Passes/StandardInstrumentations.h
@@ -22,10 +22,10 @@
#include "llvm/CodeGen/MachineBasicBlock.h"
#include "llvm/IR/BasicBlock.h"
#include "llvm/IR/DebugInfoMetadata.h"
+#include "llvm/IR/DroppedVariableStatsIR.h"
#include "llvm/IR/OptBisect.h"
#include "llvm/IR/PassTimingInfo.h"
#include "llvm/IR/ValueHandle.h"
-#include "llvm/Passes/DroppedVariableStatsIR.h"
#include "llvm/Support/CommandLine.h"
#include "llvm/Support/TimeProfiler.h"
#include "llvm/Transforms/IPO/SampleProfileProbe.h"
diff --git a/llvm/lib/IR/CMakeLists.txt b/llvm/lib/IR/CMakeLists.txt
index 5f6254b231318..eb00829fd8c70 100644
--- a/llvm/lib/IR/CMakeLists.txt
+++ b/llvm/lib/IR/CMakeLists.txt
@@ -26,6 +26,8 @@ add_llvm_component_library(LLVMCore
DiagnosticInfo.cpp
DiagnosticPrinter.cpp
Dominators.cpp
+ DroppedVariableStats.cpp
+ DroppedVariableStatsIR.cpp
EHPersonalities.cpp
FPEnv.cpp
Function.cpp
diff --git a/llvm/lib/IR/DroppedVariableStats.cpp b/llvm/lib/IR/DroppedVariableStats.cpp
new file mode 100644
index 0000000000000..d80ac9339a1b2
--- /dev/null
+++ b/llvm/lib/IR/DroppedVariableStats.cpp
@@ -0,0 +1,147 @@
+///===- DroppedVariableStats.cpp ----------------------------------------===//
+///
+/// Part of the LLVM Project, under the Apache License v2.0 with LLVM
+/// Exceptions. See https://llvm.org/LICENSE.txt for license information.
+/// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+///
+///===---------------------------------------------------------------------===//
+/// \file
+/// Dropped Variable Statistics for Debug Information. Reports any number
+/// of #dbg_value that get dropped due to an optimization pass.
+///
+///===---------------------------------------------------------------------===//
+
+#include "llvm/IR/DroppedVariableStats.h"
+#include "llvm/IR/DebugInfoMetadata.h"
+#include "llvm/IR/DiagnosticInfo.h"
+#include "llvm/IR/Function.h"
+
+using namespace llvm;
+
+DroppedVariableStats::DroppedVariableStats(bool DroppedVarStatsEnabled)
+ : DroppedVariableStatsEnabled(DroppedVarStatsEnabled) {
+ if (DroppedVarStatsEnabled)
+ llvm::outs() << "Pass Level, Pass Name, Num of Dropped Variables, Func or "
+ "Module Name\n";
+}
+
+void DroppedVariableStats::setup() {
+ DebugVariablesStack.push_back({DenseMap<const Function *, DebugVariables>()});
+ InlinedAts.push_back({DenseMap<StringRef, DenseMap<VarID, DILocation *>>()});
+}
+
+void DroppedVariableStats::cleanup() {
+ assert(!DebugVariablesStack.empty() &&
+ "DebugVariablesStack shouldn't be empty!");
+ assert(!InlinedAts.empty() && "InlinedAts shouldn't be empty!");
+ DebugVariablesStack.pop_back();
+ InlinedAts.pop_back();
+}
+
+void DroppedVariableStats::calculateDroppedStatsAndPrint(
+ DebugVariables &DbgVariables, StringRef FuncName, StringRef PassID,
+ StringRef FuncOrModName, StringRef PassLevel, const Function *Func) {
+ unsigned DroppedCount = 0;
+ DenseSet<VarID> &DebugVariablesBeforeSet = DbgVariables.DebugVariablesBefore;
+ DenseSet<VarID> &DebugVariablesAfterSet = DbgVariables.DebugVariablesAfter;
+ if (InlinedAts.back().find(FuncName) == InlinedAts.back().end())
+ return;
+ DenseMap<VarID, DILocation *> &InlinedAtsMap = InlinedAts.back()[FuncName];
+ // Find an Instruction that shares the same scope as the dropped #dbg_value
+ // or has a scope that is the child of the scope of the #dbg_value, and has
+ // an inlinedAt equal to the inlinedAt of the #dbg_value or it's inlinedAt
+ // chain contains the inlinedAt of the #dbg_value, if such an Instruction is
+ // found, debug information is dropped.
+ for (VarID Var : DebugVariablesBeforeSet) {
+ if (DebugVariablesAfterSet.contains(Var))
+ continue;
+ visitEveryInstruction(DroppedCount, InlinedAtsMap, Var);
+ removeVarFromAllSets(Var, Func);
+ }
+ if (DroppedCount > 0) {
+ llvm::outs() << PassLevel << ", " << PassID << ", " << DroppedCount << ", "
+ << FuncOrModName << "\n";
+ PassDroppedVariables = true;
+ } else
+ PassDroppedVariables = false;
+}
+
+bool DroppedVariableStats::updateDroppedCount(
+ DILocation *DbgLoc, const DIScope *Scope, const DIScope *DbgValScope,
+ DenseMap<VarID, DILocation *> &InlinedAtsMap, VarID Var,
+ unsigned &DroppedCount) {
+ // If the Scope is a child of, or equal to the DbgValScope and is inlined at
+ // the Var's InlinedAt location, return true to signify that the Var has
+ // been dropped.
+ if (isScopeChildOfOrEqualTo(Scope, DbgValScope))
+ if (isInlinedAtChildOfOrEqualTo(DbgLoc->getInlinedAt(),
+ InlinedAtsMap[Var])) {
+ // Found another instruction in the variable's scope, so there exists a
+ // break point at which the variable could be observed. Count it as
+ // dropped.
+ DroppedCount++;
+ return true;
+ }
+ return false;
+}
+
+void DroppedVariableStats::run(DebugVariables &DbgVariables, StringRef FuncName,
+ bool Before) {
+ auto &VarIDSet = (Before ? DbgVariables.DebugVariablesBefore
+ : DbgVariables.DebugVariablesAfter);
+ auto &InlinedAtsMap = InlinedAts.back();
+ if (Before)
+ InlinedAtsMap.try_emplace(FuncName, DenseMap<VarID, DILocation *>());
+ VarIDSet = DenseSet<VarID>();
+ visitEveryDebugRecord(VarIDSet, InlinedAtsMap, FuncName, Before);
+}
+
+void DroppedVariableStats::populateVarIDSetAndInlinedMap(
+ const DILocalVariable *DbgVar, DebugLoc DbgLoc, DenseSet<VarID> &VarIDSet,
+ DenseMap<StringRef, DenseMap<VarID, DILocation *>> &InlinedAtsMap,
+ StringRef FuncName, bool Before) {
+ VarID Key{DbgVar->getScope(), DbgLoc->getInlinedAtScope(), DbgVar};
+ VarIDSet.insert(Key);
+ if (Before)
+ InlinedAtsMap[FuncName].try_emplace(Key, DbgLoc.getInlinedAt());
+}
+
+void DroppedVariableStats::removeVarFromAllSets(VarID Var, const Function *F) {
+ // Do not remove Var from the last element, it will be popped from the
+ // stack.
+ for (auto &DebugVariablesMap : llvm::drop_end(DebugVariablesStack))
+ DebugVariablesMap[F].DebugVariablesBefore.erase(Var);
+}
+
+bool DroppedVariableStats::isScopeChildOfOrEqualTo(const DIScope *Scope,
+ const DIScope *DbgValScope) {
+ while (Scope != nullptr) {
+ if (VisitedScope.find(Scope) == VisitedScope.end()) {
+ VisitedScope.insert(Scope);
+ if (Scope == DbgValScope) {
+ VisitedScope.clear();
+ return true;
+ }
+ Scope = Scope->getScope();
+ } else {
+ VisitedScope.clear();
+ return false;
+ }
+ }
+ return false;
+}
+
+bool DroppedVariableStats::isInlinedAtChildOfOrEqualTo(
+ const DILocation *InlinedAt, const DILocation *DbgValInlinedAt) {
+ if (DbgValInlinedAt == InlinedAt)
+ return true;
+ if (!DbgValInlinedAt)
+ return false;
+ auto *IA = InlinedAt;
+ while (IA) {
+ if (IA == DbgValInlinedAt)
+ return true;
+ IA = IA->getInlinedAt();
+ }
+ return false;
+}
diff --git a/llvm/lib/Passes/DroppedVariableStatsIR.cpp b/llvm/lib/IR/DroppedVariableStatsIR.cpp
similarity index 70%
rename from llvm/lib/Passes/DroppedVariableStatsIR.cpp
rename to llvm/lib/IR/DroppedVariableStatsIR.cpp
index e1c277e87efb3..382a024c3ee15 100644
--- a/llvm/lib/Passes/DroppedVariableStatsIR.cpp
+++ b/llvm/lib/IR/DroppedVariableStatsIR.cpp
@@ -11,10 +11,48 @@
///
///===---------------------------------------------------------------------===//
-#include "llvm/Passes/DroppedVariableStatsIR.h"
+#include "llvm/IR/DroppedVariableStatsIR.h"
+#include "llvm/IR/DebugInfoMetadata.h"
+#include "llvm/IR/InstIterator.h"
+#include "llvm/IR/Module.h"
+#include "llvm/IR/PassInstrumentation.h"
using namespace llvm;
+template <typename IRUnitT>
+const IRUnitT *DroppedVariableStatsIR::unwrapIR(Any IR) {
+ const IRUnitT **IRPtr = llvm::any_cast<const IRUnitT *>(&IR);
+ return IRPtr ? *IRPtr : nullptr;
+}
+
+void DroppedVariableStatsIR::runBeforePass(StringRef P, Any IR) {
+ setup();
+ if (const auto *M = unwrapIR<Module>(IR))
+ return this->runOnModule(P, M, true);
+ if (const auto *F = unwrapIR<Function>(IR))
+ return this->runOnFunction(P, F, true);
+}
+
+void DroppedVariableStatsIR::runAfterPass(StringRef P, Any IR) {
+ if (const auto *M = unwrapIR<Module>(IR))
+ runAfterPassModule(P, M);
+ else if (const auto *F = unwrapIR<Function>(IR))
+ runAfterPassFunction(P, F);
+ cleanup();
+}
+
+void DroppedVariableStatsIR::runAfterPassFunction(StringRef PassID,
+ const Function *F) {
+ runOnFunction(PassID, F, false);
+ calculateDroppedVarStatsOnFunction(F, PassID, F->getName().str(), "Function");
+}
+
+void DroppedVariableStatsIR::runAfterPassModule(StringRef PassID,
+ const Module *M) {
+ runOnModule(PassID, M, false);
+ calculateDroppedVarStatsOnModule(M, PassID, M->getName().str(), "Module");
+}
+
void DroppedVariableStatsIR::runOnFunction(StringRef PassID, const Function *F,
bool Before) {
auto &DebugVariables = DebugVariablesStack.back()[F];
diff --git a/llvm/lib/Passes/CMakeLists.txt b/llvm/lib/Passes/CMakeLists.txt
index 23799ac4f98f7..6425f4934b210 100644
--- a/llvm/lib/Passes/CMakeLists.txt
+++ b/llvm/lib/Passes/CMakeLists.txt
@@ -1,6 +1,5 @@
add_llvm_component_library(LLVMPasses
CodeGenPassBuilder.cpp
- DroppedVariableStatsIR.cpp
OptimizationLevel.cpp
PassBuilder.cpp
PassBuilderBindings.cpp
>From 94f4cf922deb8997ff10525b58432cf2eab8bee2 Mon Sep 17 00:00:00 2001
From: Shubham Sandeep Rastogi <srastogi22 at apple.com>
Date: Mon, 10 Feb 2025 19:41:46 -0800
Subject: [PATCH 2/2] Add a pass to collect dropped var stats for MIR
This patch uses the DroppedVariableStats class to add dropped variable
statistics for MIR passes.
Reland 44de16fdbc0a9d897ac0945108c8213d2a01ffd5
---
.../llvm/CodeGen/DroppedVariableStatsMIR.h | 59 +
llvm/lib/CodeGen/CMakeLists.txt | 1 +
llvm/lib/CodeGen/DroppedVariableStatsMIR.cpp | 95 ++
llvm/lib/CodeGen/MachineFunctionPass.cpp | 17 +-
llvm/unittests/CodeGen/CMakeLists.txt | 1 +
.../CodeGen/DroppedVariableStatsMIRTest.cpp | 1081 +++++++++++++++++
6 files changed, 1253 insertions(+), 1 deletion(-)
create mode 100644 llvm/include/llvm/CodeGen/DroppedVariableStatsMIR.h
create mode 100644 llvm/lib/CodeGen/DroppedVariableStatsMIR.cpp
create mode 100644 llvm/unittests/CodeGen/DroppedVariableStatsMIRTest.cpp
diff --git a/llvm/include/llvm/CodeGen/DroppedVariableStatsMIR.h b/llvm/include/llvm/CodeGen/DroppedVariableStatsMIR.h
new file mode 100644
index 0000000000000..4285c594ce1e4
--- /dev/null
+++ b/llvm/include/llvm/CodeGen/DroppedVariableStatsMIR.h
@@ -0,0 +1,59 @@
+///===- DroppedVariableStatsMIR.h - Opt Diagnostics -*- C++ -*-------------===//
+///
+/// Part of the LLVM Project, under the Apache License v2.0 with LLVM
+/// Exceptions. See https://llvm.org/LICENSE.txt for license information.
+/// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+///
+///===---------------------------------------------------------------------===//
+/// \file
+/// Dropped Variable Statistics for Debug Information. Reports any number
+/// of DBG_VALUEs that get dropped due to an optimization pass.
+///
+///===---------------------------------------------------------------------===//
+
+#ifndef LLVM_CODEGEN_DROPPEDVARIABLESTATSMIR_H
+#define LLVM_CODEGEN_DROPPEDVARIABLESTATSMIR_H
+
+#include "llvm/CodeGen/MachineFunction.h"
+#include "llvm/IR/DroppedVariableStats.h"
+
+namespace llvm {
+
+/// A class to collect and print dropped debug information due to MIR
+/// optimization passes. After every MIR pass is run, it will print how many
+/// #DBG_VALUEs were dropped due to that pass.
+class DroppedVariableStatsMIR : public DroppedVariableStats {
+public:
+ DroppedVariableStatsMIR() : llvm::DroppedVariableStats(false) {}
+
+ void runBeforePass(StringRef PassID, MachineFunction *MF);
+
+ void runAfterPass(StringRef PassID, MachineFunction *MF);
+
+private:
+ const MachineFunction *MFunc;
+ /// Populate DebugVariablesBefore, DebugVariablesAfter, InlinedAts before or
+ /// after a pass has run to facilitate dropped variable calculation for an
+ /// llvm::MachineFunction.
+ void runOnMachineFunction(const MachineFunction *MF, bool Before);
+ /// Iterate over all Instructions in a MachineFunction and report any dropped
+ /// debug information.
+ void calculateDroppedVarStatsOnMachineFunction(const MachineFunction *MF,
+ StringRef PassID,
+ StringRef FuncOrModName);
+ /// Override base class method to run on an llvm::MachineFunction
+ /// specifically.
+ virtual void
+ visitEveryInstruction(unsigned &DroppedCount,
+ DenseMap<VarID, DILocation *> &InlinedAtsMap,
+ VarID Var) override;
+ /// Override base class method to run on DBG_VALUEs specifically.
+ virtual void visitEveryDebugRecord(
+ DenseSet<VarID> &VarIDSet,
+ DenseMap<StringRef, DenseMap<VarID, DILocation *>> &InlinedAtsMap,
+ StringRef FuncName, bool Before) override;
+};
+
+} // namespace llvm
+
+#endif
diff --git a/llvm/lib/CodeGen/CMakeLists.txt b/llvm/lib/CodeGen/CMakeLists.txt
index 88f863d8204d0..23ec3310079d3 100644
--- a/llvm/lib/CodeGen/CMakeLists.txt
+++ b/llvm/lib/CodeGen/CMakeLists.txt
@@ -50,6 +50,7 @@ add_llvm_component_library(LLVMCodeGen
DeadMachineInstructionElim.cpp
DetectDeadLanes.cpp
DFAPacketizer.cpp
+ DroppedVariableStatsMIR.cpp
DwarfEHPrepare.cpp
EarlyIfConversion.cpp
EdgeBundles.cpp
diff --git a/llvm/lib/CodeGen/DroppedVariableStatsMIR.cpp b/llvm/lib/CodeGen/DroppedVariableStatsMIR.cpp
new file mode 100644
index 0000000000000..9a1d4fb5d888a
--- /dev/null
+++ b/llvm/lib/CodeGen/DroppedVariableStatsMIR.cpp
@@ -0,0 +1,95 @@
+///===- DroppedVariableStatsMIR.cpp ---------------------------------------===//
+///
+/// Part of the LLVM Project, under the Apache License v2.0 with LLVM
+/// Exceptions. See https://llvm.org/LICENSE.txt for license information.
+/// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+///
+///===---------------------------------------------------------------------===//
+/// \file
+/// Dropped Variable Statistics for Debug Information. Reports any number
+/// of DBG_VALUEs that get dropped due to an optimization pass.
+///
+///===---------------------------------------------------------------------===//
+
+#include "llvm/CodeGen/DroppedVariableStatsMIR.h"
+#include "llvm/IR/DebugInfoMetadata.h"
+
+using namespace llvm;
+
+void DroppedVariableStatsMIR::runBeforePass(StringRef PassID,
+ MachineFunction *MF) {
+ if (PassID == "Debug Variable Analysis")
+ return;
+ setup();
+ return runOnMachineFunction(MF, true);
+}
+
+void DroppedVariableStatsMIR::runAfterPass(StringRef PassID,
+ MachineFunction *MF) {
+ if (PassID == "Debug Variable Analysis")
+ return;
+ runOnMachineFunction(MF, false);
+ calculateDroppedVarStatsOnMachineFunction(MF, PassID, MF->getName().str());
+ cleanup();
+}
+
+void DroppedVariableStatsMIR::runOnMachineFunction(const MachineFunction *MF,
+ bool Before) {
+ auto &DebugVariables = DebugVariablesStack.back()[&MF->getFunction()];
+ auto FuncName = MF->getName();
+ MFunc = MF;
+ run(DebugVariables, FuncName, Before);
+}
+
+void DroppedVariableStatsMIR::calculateDroppedVarStatsOnMachineFunction(
+ const MachineFunction *MF, StringRef PassID, StringRef FuncOrModName) {
+ MFunc = MF;
+ StringRef FuncName = MF->getName();
+ const Function *Func = &MF->getFunction();
+ DebugVariables &DbgVariables = DebugVariablesStack.back()[Func];
+ calculateDroppedStatsAndPrint(DbgVariables, FuncName, PassID, FuncOrModName,
+ "MachineFunction", Func);
+}
+
+void DroppedVariableStatsMIR::visitEveryInstruction(
+ unsigned &DroppedCount, DenseMap<VarID, DILocation *> &InlinedAtsMap,
+ VarID Var) {
+ unsigned PrevDroppedCount = DroppedCount;
+ const DIScope *DbgValScope = std::get<0>(Var);
+ for (const auto &MBB : *MFunc) {
+ for (const auto &MI : MBB) {
+ if (!MI.isDebugInstr()) {
+ auto *DbgLoc = MI.getDebugLoc().get();
+ if (!DbgLoc)
+ continue;
+
+ auto *Scope = DbgLoc->getScope();
+ if (updateDroppedCount(DbgLoc, Scope, DbgValScope, InlinedAtsMap, Var,
+ DroppedCount))
+ break;
+ }
+ }
+ if (PrevDroppedCount != DroppedCount) {
+ PrevDroppedCount = DroppedCount;
+ break;
+ }
+ }
+}
+
+void DroppedVariableStatsMIR::visitEveryDebugRecord(
+ DenseSet<VarID> &VarIDSet,
+ DenseMap<StringRef, DenseMap<VarID, DILocation *>> &InlinedAtsMap,
+ StringRef FuncName, bool Before) {
+ for (const auto &MBB : *MFunc) {
+ for (const auto &MI : MBB) {
+ if (MI.isDebugValueLike()) {
+ auto *DbgVar = MI.getDebugVariable();
+ if (!DbgVar)
+ continue;
+ auto DbgLoc = MI.getDebugLoc();
+ populateVarIDSetAndInlinedMap(DbgVar, DbgLoc, VarIDSet, InlinedAtsMap,
+ FuncName, Before);
+ }
+ }
+ }
+}
diff --git a/llvm/lib/CodeGen/MachineFunctionPass.cpp b/llvm/lib/CodeGen/MachineFunctionPass.cpp
index 62ac3e32d24d9..a669877985821 100644
--- a/llvm/lib/CodeGen/MachineFunctionPass.cpp
+++ b/llvm/lib/CodeGen/MachineFunctionPass.cpp
@@ -20,6 +20,7 @@
#include "llvm/Analysis/OptimizationRemarkEmitter.h"
#include "llvm/Analysis/ScalarEvolution.h"
#include "llvm/Analysis/ScalarEvolutionAliasAnalysis.h"
+#include "llvm/CodeGen/DroppedVariableStatsMIR.h"
#include "llvm/CodeGen/MachineFunction.h"
#include "llvm/CodeGen/MachineModuleInfo.h"
#include "llvm/CodeGen/MachineOptimizationRemarkEmitter.h"
@@ -32,6 +33,11 @@
using namespace llvm;
using namespace ore;
+static cl::opt<bool> DroppedVarStatsMIR(
+ "dropped-variable-stats-mir", cl::Hidden,
+ cl::desc("Dump dropped debug variables stats for MIR passes"),
+ cl::init(false));
+
Pass *MachineFunctionPass::createPrinterPass(raw_ostream &O,
const std::string &Banner) const {
return createMachineFunctionPrinterPass(O, Banner);
@@ -91,7 +97,16 @@ bool MachineFunctionPass::runOnFunction(Function &F) {
MFProps.reset(ClearedProperties);
- bool RV = runOnMachineFunction(MF);
+ bool RV;
+ if (DroppedVarStatsMIR) {
+ DroppedVariableStatsMIR DroppedVarStatsMF;
+ auto PassName = getPassName();
+ DroppedVarStatsMF.runBeforePass(PassName, &MF);
+ RV = runOnMachineFunction(MF);
+ DroppedVarStatsMF.runAfterPass(PassName, &MF);
+ } else {
+ RV = runOnMachineFunction(MF);
+ }
if (ShouldEmitSizeRemarks) {
// We wanted size remarks. Check if there was a change to the number of
diff --git a/llvm/unittests/CodeGen/CMakeLists.txt b/llvm/unittests/CodeGen/CMakeLists.txt
index 963cdcc0275e1..4f580e7539f4d 100644
--- a/llvm/unittests/CodeGen/CMakeLists.txt
+++ b/llvm/unittests/CodeGen/CMakeLists.txt
@@ -27,6 +27,7 @@ add_llvm_unittest(CodeGenTests
CCStateTest.cpp
DIEHashTest.cpp
DIETest.cpp
+ DroppedVariableStatsMIRTest.cpp
DwarfStringPoolEntryRefTest.cpp
InstrRefLDVTest.cpp
LowLevelTypeTest.cpp
diff --git a/llvm/unittests/CodeGen/DroppedVariableStatsMIRTest.cpp b/llvm/unittests/CodeGen/DroppedVariableStatsMIRTest.cpp
new file mode 100644
index 0000000000000..157060ec4eebe
--- /dev/null
+++ b/llvm/unittests/CodeGen/DroppedVariableStatsMIRTest.cpp
@@ -0,0 +1,1081 @@
+//===- unittests/CodeGen/DroppedVariableStatsMIRTest.cpp ------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#include "llvm/CodeGen/DroppedVariableStatsMIR.h"
+#include "llvm/AsmParser/Parser.h"
+#include "llvm/CodeGen/MIRParser/MIRParser.h"
+#include "llvm/CodeGen/MachineModuleInfo.h"
+#include "llvm/IR/Function.h"
+#include "llvm/IR/LegacyPassManager.h"
+#include "llvm/IR/Module.h"
+#include "llvm/MC/TargetRegistry.h"
+#include "llvm/Pass.h"
+#include "llvm/Support/SourceMgr.h"
+#include "llvm/Support/TargetSelect.h"
+#include "llvm/Target/TargetMachine.h"
+#include "gtest/gtest.h"
+#include <gtest/gtest.h>
+#include <llvm/ADT/SmallString.h>
+#include <llvm/IR/LLVMContext.h>
+#include <llvm/IR/Module.h>
+#include <llvm/IR/PassInstrumentation.h>
+#include <llvm/IR/PassManager.h>
+#include <llvm/IR/PassTimingInfo.h>
+#include <llvm/Support/raw_ostream.h>
+
+using namespace llvm;
+
+namespace {
+
+std::unique_ptr<TargetMachine>
+createTargetMachine(std::string TT, StringRef CPU, StringRef FS) {
+ std::string Error;
+ const Target *T = TargetRegistry::lookupTarget(TT, Error);
+ if (!T)
+ return nullptr;
+ TargetOptions Options;
+ return std::unique_ptr<TargetMachine>(
+ static_cast<TargetMachine *>(T->createTargetMachine(
+ TT, CPU, FS, Options, std::nullopt, std::nullopt)));
+}
+
+std::unique_ptr<Module> parseMIR(const TargetMachine &TM, StringRef MIRCode,
+ MachineModuleInfo &MMI, LLVMContext *Context) {
+ SMDiagnostic Diagnostic;
+ std::unique_ptr<Module> M;
+ std::unique_ptr<MemoryBuffer> MBuffer = MemoryBuffer::getMemBuffer(MIRCode);
+ auto MIR = createMIRParser(std::move(MBuffer), *Context);
+ if (!MIR)
+ return nullptr;
+
+ std::unique_ptr<Module> Mod = MIR->parseIRModule();
+ if (!Mod)
+ return nullptr;
+
+ Mod->setDataLayout(TM.createDataLayout());
+
+ if (MIR->parseMachineFunctions(*Mod, MMI)) {
+ M.reset();
+ return nullptr;
+ }
+ return Mod;
+}
+// This test ensures that if a DBG_VALUE and an instruction that exists in the
+// same scope as that DBG_VALUE are both deleted as a result of an optimization
+// pass, debug information is considered not dropped.
+TEST(DroppedVariableStatsMIR, BothDeleted) {
+ InitializeAllTargetInfos();
+ InitializeAllTargets();
+ InitializeAllTargetMCs();
+ PassInstrumentationCallbacks PIC;
+ PassInstrumentation PI(&PIC);
+
+ LLVMContext C;
+
+ const char *MIR =
+ R"(
+--- |
+ ; ModuleID = '/tmp/test.ll'
+ source_filename = "/tmp/test.ll"
+ target datalayout = "e-m:o-p270:32:32-p271:32:32-p272:64:64-i64:64-i128:128-n32:64-S128-Fn32"
+
+ define noundef range(i32 -2147483647, -2147483648) i32 @_Z3fooi(i32 noundef %x) local_unnamed_addr !dbg !4 {
+ entry:
+ #dbg_value(i32 %x, !10, !DIExpression(), !11)
+ %add = add nsw i32 %x, 1, !dbg !12
+ ret i32 0
+ }
+
+ !llvm.dbg.cu = !{!0}
+ !llvm.module.flags = !{!2}
+ !llvm.ident = !{!3}
+
+ !0 = distinct !DICompileUnit(language: DW_LANG_C_plus_plus_14, file: !1, producer: "clang", isOptimized: true, runtimeVersion: 0, emissionKind: FullDebug, splitDebugInlining: false, nameTableKind: Apple, sysroot: "/")
+ !1 = !DIFile(filename: "/tmp/code.cpp", directory: "/")
+ !2 = !{i32 2, !"Debug Info Version", i32 3}
+ !3 = !{!"clang"}
+ !4 = distinct !DISubprogram(name: "foo", linkageName: "_Z3fooi", scope: !5, file: !5, line: 1, type: !6, scopeLine: 1, spFlags: DISPFlagDefinition, unit: !0, retainedNodes: !9)
+ !5 = !DIFile(filename: "/tmp/code.cpp", directory: "")
+ !6 = !DISubroutineType(types: !7)
+ !7 = !{!8, !8}
+ !8 = !DIBasicType(name: "int", size: 32, encoding: DW_ATE_signed)
+ !9 = !{!10}
+ !10 = !DILocalVariable(name: "x", arg: 1, scope: !4, file: !5, line: 1, type: !8)
+ !11 = !DILocation(line: 0, scope: !4)
+ !12 = !DILocation(line: 2, column: 11, scope: !4)
+
+...
+---
+name: _Z3fooi
+alignment: 4
+exposesReturnsTwice: false
+legalized: false
+regBankSelected: false
+selected: false
+failedISel: false
+tracksRegLiveness: true
+hasWinCFI: false
+noPhis: false
+isSSA: true
+noVRegs: false
+hasFakeUses: false
+callsEHReturn: false
+callsUnwindInit: false
+hasEHCatchret: false
+hasEHScopes: false
+hasEHFunclets: false
+isOutlined: false
+debugInstrRef: false
+failsVerification: false
+tracksDebugUserValues: false
+registers:
+ - { id: 0, class: _, preferred-register: '', flags: [ ] }
+ - { id: 1, class: _, preferred-register: '', flags: [ ] }
+ - { id: 2, class: _, preferred-register: '', flags: [ ] }
+ - { id: 3, class: _, preferred-register: '', flags: [ ] }
+liveins:
+ - { reg: '$w0', virtual-reg: '' }
+frameInfo:
+ isFrameAddressTaken: false
+ isReturnAddressTaken: false
+ hasStackMap: false
+ hasPatchPoint: false
+ stackSize: 0
+ offsetAdjustment: 0
+ maxAlignment: 1
+ adjustsStack: false
+ hasCalls: false
+ stackProtector: ''
+ functionContext: ''
+ maxCallFrameSize: 4294967295
+ cvBytesOfCalleeSavedRegisters: 0
+ hasOpaqueSPAdjustment: false
+ hasVAStart: false
+ hasMustTailInVarArgFunc: false
+ hasTailCall: false
+ isCalleeSavedInfoValid: false
+ localFrameSize: 0
+ savePoint: ''
+ restorePoint: ''
+fixedStack: []
+stack: []
+entry_values: []
+callSites: []
+debugValueSubstitutions: []
+constants: []
+machineFunctionInfo: {}
+body: |
+ bb.1.entry:
+ liveins: $w0
+
+ %0:_(s32) = COPY $w0
+ %1:_(s32) = G_CONSTANT i32 1
+ %3:_(s32) = G_CONSTANT i32 0
+ DBG_VALUE %0(s32), $noreg, !10, !DIExpression(), debug-location !11
+ %2:_(s32) = nsw G_ADD %0, %1, debug-location !12
+ $w0 = COPY %3(s32)
+ RET_ReallyLR implicit $w0
+ )";
+ auto TM = createTargetMachine(Triple::normalize("aarch64--"), "", "");
+ if (!TM)
+ return;
+ MachineModuleInfo MMI(TM.get());
+ std::unique_ptr<Module> M = parseMIR(*TM, MIR, MMI, &C);
+ ASSERT_TRUE(M);
+
+ DroppedVariableStatsMIR Stats;
+ auto *MF = MMI.getMachineFunction(*M->getFunction("_Z3fooi"));
+ Stats.runBeforePass("Test", MF);
+
+ // This loop simulates an IR pass that drops debug information.
+ for (auto &MBB : *MF) {
+ for (auto &MI : MBB) {
+ if (MI.isDebugValueLike()) {
+ MI.eraseFromParent();
+ break;
+ }
+ }
+ for (auto &MI : MBB) {
+ auto *DbgLoc = MI.getDebugLoc().get();
+ if (DbgLoc) {
+ MI.eraseFromParent();
+ break;
+ }
+ }
+ break;
+ }
+
+ Stats.runAfterPass("Test", MF);
+ ASSERT_EQ(Stats.getPassDroppedVariables(), false);
+}
+
+// This test ensures that if a DBG_VALUE is dropped after an optimization pass,
+// but an instruction that shares the same scope as the DBG_VALUE still exists,
+// debug information is conisdered dropped.
+TEST(DroppedVariableStatsMIR, DbgValLost) {
+ InitializeAllTargetInfos();
+ InitializeAllTargets();
+ InitializeAllTargetMCs();
+ PassInstrumentationCallbacks PIC;
+ PassInstrumentation PI(&PIC);
+
+ LLVMContext C;
+
+ const char *MIR =
+ R"(
+--- |
+ ; ModuleID = '/tmp/test.ll'
+ source_filename = "/tmp/test.ll"
+ target datalayout = "e-m:o-p270:32:32-p271:32:32-p272:64:64-i64:64-i128:128-n32:64-S128-Fn32"
+
+ define noundef range(i32 -2147483647, -2147483648) i32 @_Z3fooi(i32 noundef %x) local_unnamed_addr !dbg !4 {
+ entry:
+ #dbg_value(i32 %x, !10, !DIExpression(), !11)
+ %add = add nsw i32 %x, 1, !dbg !12
+ ret i32 0
+ }
+
+ !llvm.dbg.cu = !{!0}
+ !llvm.module.flags = !{!2}
+ !llvm.ident = !{!3}
+
+ !0 = distinct !DICompileUnit(language: DW_LANG_C_plus_plus_14, file: !1, producer: "clang", isOptimized: true, runtimeVersion: 0, emissionKind: FullDebug, splitDebugInlining: false, nameTableKind: Apple, sysroot: "/")
+ !1 = !DIFile(filename: "/tmp/code.cpp", directory: "/")
+ !2 = !{i32 2, !"Debug Info Version", i32 3}
+ !3 = !{!"clang"}
+ !4 = distinct !DISubprogram(name: "foo", linkageName: "_Z3fooi", scope: !5, file: !5, line: 1, type: !6, scopeLine: 1, spFlags: DISPFlagDefinition, unit: !0, retainedNodes: !9)
+ !5 = !DIFile(filename: "/tmp/code.cpp", directory: "")
+ !6 = !DISubroutineType(types: !7)
+ !7 = !{!8, !8}
+ !8 = !DIBasicType(name: "int", size: 32, encoding: DW_ATE_signed)
+ !9 = !{!10}
+ !10 = !DILocalVariable(name: "x", arg: 1, scope: !4, file: !5, line: 1, type: !8)
+ !11 = !DILocation(line: 0, scope: !4)
+ !12 = !DILocation(line: 2, column: 11, scope: !4)
+
+...
+---
+name: _Z3fooi
+alignment: 4
+exposesReturnsTwice: false
+legalized: false
+regBankSelected: false
+selected: false
+failedISel: false
+tracksRegLiveness: true
+hasWinCFI: false
+noPhis: false
+isSSA: true
+noVRegs: false
+hasFakeUses: false
+callsEHReturn: false
+callsUnwindInit: false
+hasEHCatchret: false
+hasEHScopes: false
+hasEHFunclets: false
+isOutlined: false
+debugInstrRef: false
+failsVerification: false
+tracksDebugUserValues: false
+registers:
+ - { id: 0, class: _, preferred-register: '', flags: [ ] }
+ - { id: 1, class: _, preferred-register: '', flags: [ ] }
+ - { id: 2, class: _, preferred-register: '', flags: [ ] }
+ - { id: 3, class: _, preferred-register: '', flags: [ ] }
+liveins:
+ - { reg: '$w0', virtual-reg: '' }
+frameInfo:
+ isFrameAddressTaken: false
+ isReturnAddressTaken: false
+ hasStackMap: false
+ hasPatchPoint: false
+ stackSize: 0
+ offsetAdjustment: 0
+ maxAlignment: 1
+ adjustsStack: false
+ hasCalls: false
+ stackProtector: ''
+ functionContext: ''
+ maxCallFrameSize: 4294967295
+ cvBytesOfCalleeSavedRegisters: 0
+ hasOpaqueSPAdjustment: false
+ hasVAStart: false
+ hasMustTailInVarArgFunc: false
+ hasTailCall: false
+ isCalleeSavedInfoValid: false
+ localFrameSize: 0
+ savePoint: ''
+ restorePoint: ''
+fixedStack: []
+stack: []
+entry_values: []
+callSites: []
+debugValueSubstitutions: []
+constants: []
+machineFunctionInfo: {}
+body: |
+ bb.1.entry:
+ liveins: $w0
+
+ %0:_(s32) = COPY $w0
+ %1:_(s32) = G_CONSTANT i32 1
+ %3:_(s32) = G_CONSTANT i32 0
+ DBG_VALUE %0(s32), $noreg, !10, !DIExpression(), debug-location !11
+ %2:_(s32) = nsw G_ADD %0, %1, debug-location !12
+ $w0 = COPY %3(s32)
+ RET_ReallyLR implicit $w0
+ )";
+ auto TM = createTargetMachine(Triple::normalize("aarch64--"), "", "");
+ if (!TM)
+ return;
+ MachineModuleInfo MMI(TM.get());
+ std::unique_ptr<Module> M = parseMIR(*TM, MIR, MMI, &C);
+ ASSERT_TRUE(M);
+
+ DroppedVariableStatsMIR Stats;
+ auto *MF = MMI.getMachineFunction(*M->getFunction("_Z3fooi"));
+ Stats.runBeforePass("Test", MF);
+
+ // This loop simulates an IR pass that drops debug information.
+ for (auto &MBB : *MF) {
+ for (auto &MI : MBB) {
+ if (MI.isDebugValueLike()) {
+ MI.eraseFromParent();
+ break;
+ }
+ }
+ break;
+ }
+
+ Stats.runAfterPass("Test", MF);
+ ASSERT_EQ(Stats.getPassDroppedVariables(), true);
+}
+
+// This test ensures that if a #dbg_value is dropped after an optimization pass,
+// but an instruction that has an unrelated scope as the #dbg_value still
+// exists, debug information is conisdered not dropped.
+TEST(DroppedVariableStatsMIR, UnrelatedScopes) {
+ InitializeAllTargetInfos();
+ InitializeAllTargets();
+ InitializeAllTargetMCs();
+ PassInstrumentationCallbacks PIC;
+ PassInstrumentation PI(&PIC);
+
+ LLVMContext C;
+
+ const char *MIR =
+ R"(
+--- |
+ ; ModuleID = '/tmp/test.ll'
+ source_filename = "/tmp/test.ll"
+ target datalayout = "e-m:o-p270:32:32-p271:32:32-p272:64:64-i64:64-i128:128-n32:64-S128-Fn32"
+
+ define noundef range(i32 -2147483647, -2147483648) i32 @_Z3fooi(i32 noundef %x) local_unnamed_addr !dbg !4 {
+ entry:
+ #dbg_value(i32 %x, !10, !DIExpression(), !11)
+ %add = add nsw i32 %x, 1, !dbg !12
+ ret i32 0
+ }
+
+ !llvm.dbg.cu = !{!0}
+ !llvm.module.flags = !{!2}
+ !llvm.ident = !{!3}
+
+ !0 = distinct !DICompileUnit(language: DW_LANG_C_plus_plus_14, file: !1, producer: "clang", isOptimized: true, runtimeVersion: 0, emissionKind: FullDebug, splitDebugInlining: false, nameTableKind: Apple, sysroot: "/")
+ !1 = !DIFile(filename: "/tmp/code.cpp", directory: "/")
+ !2 = !{i32 2, !"Debug Info Version", i32 3}
+ !3 = !{!"clang"}
+ !4 = distinct !DISubprogram(name: "foo", linkageName: "_Z3fooi", scope: !5, file: !5, line: 1, type: !6, scopeLine: 1, spFlags: DISPFlagDefinition, unit: !0, retainedNodes: !9)
+ !5 = !DIFile(filename: "/tmp/code.cpp", directory: "")
+ !6 = !DISubroutineType(types: !7)
+ !7 = !{!8, !8}
+ !8 = !DIBasicType(name: "int", size: 32, encoding: DW_ATE_signed)
+ !9 = !{!10}
+ !10 = !DILocalVariable(name: "x", arg: 1, scope: !4, file: !5, line: 1, type: !8)
+ !11 = !DILocation(line: 0, scope: !4)
+ !12 = !DILocation(line: 2, column: 11, scope: !13)
+ !13 = distinct !DISubprogram(name: "bar", linkageName: "_Z3bari", scope: !5, file: !5, line: 1, type: !6, scopeLine: 1, spFlags: DISPFlagDefinition, unit: !0, retainedNodes: !9)
+
+...
+---
+name: _Z3fooi
+alignment: 4
+exposesReturnsTwice: false
+legalized: false
+regBankSelected: false
+selected: false
+failedISel: false
+tracksRegLiveness: true
+hasWinCFI: false
+noPhis: false
+isSSA: true
+noVRegs: false
+hasFakeUses: false
+callsEHReturn: false
+callsUnwindInit: false
+hasEHCatchret: false
+hasEHScopes: false
+hasEHFunclets: false
+isOutlined: false
+debugInstrRef: false
+failsVerification: false
+tracksDebugUserValues: false
+registers:
+ - { id: 0, class: _, preferred-register: '', flags: [ ] }
+ - { id: 1, class: _, preferred-register: '', flags: [ ] }
+ - { id: 2, class: _, preferred-register: '', flags: [ ] }
+ - { id: 3, class: _, preferred-register: '', flags: [ ] }
+liveins:
+ - { reg: '$w0', virtual-reg: '' }
+frameInfo:
+ isFrameAddressTaken: false
+ isReturnAddressTaken: false
+ hasStackMap: false
+ hasPatchPoint: false
+ stackSize: 0
+ offsetAdjustment: 0
+ maxAlignment: 1
+ adjustsStack: false
+ hasCalls: false
+ stackProtector: ''
+ functionContext: ''
+ maxCallFrameSize: 4294967295
+ cvBytesOfCalleeSavedRegisters: 0
+ hasOpaqueSPAdjustment: false
+ hasVAStart: false
+ hasMustTailInVarArgFunc: false
+ hasTailCall: false
+ isCalleeSavedInfoValid: false
+ localFrameSize: 0
+ savePoint: ''
+ restorePoint: ''
+fixedStack: []
+stack: []
+entry_values: []
+callSites: []
+debugValueSubstitutions: []
+constants: []
+machineFunctionInfo: {}
+body: |
+ bb.1.entry:
+ liveins: $w0
+
+ %0:_(s32) = COPY $w0
+ %1:_(s32) = G_CONSTANT i32 1
+ %3:_(s32) = G_CONSTANT i32 0
+ DBG_VALUE %0(s32), $noreg, !10, !DIExpression(), debug-location !11
+ %2:_(s32) = nsw G_ADD %0, %1, debug-location !12
+ $w0 = COPY %3(s32)
+ RET_ReallyLR implicit $w0
+ )";
+ auto TM = createTargetMachine(Triple::normalize("aarch64--"), "", "");
+ if (!TM)
+ return;
+ MachineModuleInfo MMI(TM.get());
+ std::unique_ptr<Module> M = parseMIR(*TM, MIR, MMI, &C);
+ ASSERT_TRUE(M);
+
+ DroppedVariableStatsMIR Stats;
+ auto *MF = MMI.getMachineFunction(*M->getFunction("_Z3fooi"));
+ Stats.runBeforePass("Test", MF);
+
+ // This loop simulates an IR pass that drops debug information.
+ for (auto &MBB : *MF) {
+ for (auto &MI : MBB) {
+ if (MI.isDebugValueLike()) {
+ MI.eraseFromParent();
+ break;
+ }
+ }
+ break;
+ }
+
+ Stats.runAfterPass("Test", MF);
+ ASSERT_EQ(Stats.getPassDroppedVariables(), false);
+}
+
+// This test ensures that if a #dbg_value is dropped after an optimization pass,
+// but an instruction that has a scope which is a child of the #dbg_value scope
+// still exists, debug information is conisdered dropped.
+TEST(DroppedVariableStatsMIR, ChildScopes) {
+ InitializeAllTargetInfos();
+ InitializeAllTargets();
+ InitializeAllTargetMCs();
+ PassInstrumentationCallbacks PIC;
+ PassInstrumentation PI(&PIC);
+
+ LLVMContext C;
+
+ const char *MIR =
+ R"(
+--- |
+ ; ModuleID = '/tmp/test.ll'
+ source_filename = "/tmp/test.ll"
+ target datalayout = "e-m:o-p270:32:32-p271:32:32-p272:64:64-i64:64-i128:128-n32:64-S128-Fn32"
+
+ define noundef range(i32 -2147483647, -2147483648) i32 @_Z3fooi(i32 noundef %x) local_unnamed_addr !dbg !4 {
+ entry:
+ #dbg_value(i32 %x, !10, !DIExpression(), !11)
+ %add = add nsw i32 %x, 1, !dbg !12
+ ret i32 0
+ }
+
+ !llvm.dbg.cu = !{!0}
+ !llvm.module.flags = !{!2}
+ !llvm.ident = !{!3}
+
+ !0 = distinct !DICompileUnit(language: DW_LANG_C_plus_plus_14, file: !1, producer: "clang", isOptimized: true, runtimeVersion: 0, emissionKind: FullDebug, splitDebugInlining: false, nameTableKind: Apple, sysroot: "/")
+ !1 = !DIFile(filename: "/tmp/code.cpp", directory: "/")
+ !2 = !{i32 2, !"Debug Info Version", i32 3}
+ !3 = !{!"clang"}
+ !4 = distinct !DISubprogram(name: "foo", linkageName: "_Z3fooi", scope: !5, file: !5, line: 1, type: !6, scopeLine: 1, spFlags: DISPFlagDefinition, unit: !0, retainedNodes: !9)
+ !5 = !DIFile(filename: "/tmp/code.cpp", directory: "")
+ !6 = !DISubroutineType(types: !7)
+ !7 = !{!8, !8}
+ !8 = !DIBasicType(name: "int", size: 32, encoding: DW_ATE_signed)
+ !9 = !{!10}
+ !10 = !DILocalVariable(name: "x", arg: 1, scope: !4, file: !5, line: 1, type: !8)
+ !11 = !DILocation(line: 0, scope: !4)
+ !12 = !DILocation(line: 2, column: 11, scope: !13)
+ !13 = distinct !DILexicalBlock(scope: !4, file: !5, line: 10, column: 28)
+
+...
+---
+name: _Z3fooi
+alignment: 4
+exposesReturnsTwice: false
+legalized: false
+regBankSelected: false
+selected: false
+failedISel: false
+tracksRegLiveness: true
+hasWinCFI: false
+noPhis: false
+isSSA: true
+noVRegs: false
+hasFakeUses: false
+callsEHReturn: false
+callsUnwindInit: false
+hasEHCatchret: false
+hasEHScopes: false
+hasEHFunclets: false
+isOutlined: false
+debugInstrRef: false
+failsVerification: false
+tracksDebugUserValues: false
+registers:
+ - { id: 0, class: _, preferred-register: '', flags: [ ] }
+ - { id: 1, class: _, preferred-register: '', flags: [ ] }
+ - { id: 2, class: _, preferred-register: '', flags: [ ] }
+ - { id: 3, class: _, preferred-register: '', flags: [ ] }
+liveins:
+ - { reg: '$w0', virtual-reg: '' }
+frameInfo:
+ isFrameAddressTaken: false
+ isReturnAddressTaken: false
+ hasStackMap: false
+ hasPatchPoint: false
+ stackSize: 0
+ offsetAdjustment: 0
+ maxAlignment: 1
+ adjustsStack: false
+ hasCalls: false
+ stackProtector: ''
+ functionContext: ''
+ maxCallFrameSize: 4294967295
+ cvBytesOfCalleeSavedRegisters: 0
+ hasOpaqueSPAdjustment: false
+ hasVAStart: false
+ hasMustTailInVarArgFunc: false
+ hasTailCall: false
+ isCalleeSavedInfoValid: false
+ localFrameSize: 0
+ savePoint: ''
+ restorePoint: ''
+fixedStack: []
+stack: []
+entry_values: []
+callSites: []
+debugValueSubstitutions: []
+constants: []
+machineFunctionInfo: {}
+body: |
+ bb.1.entry:
+ liveins: $w0
+
+ %0:_(s32) = COPY $w0
+ %1:_(s32) = G_CONSTANT i32 1
+ %3:_(s32) = G_CONSTANT i32 0
+ DBG_VALUE %0(s32), $noreg, !10, !DIExpression(), debug-location !11
+ %2:_(s32) = nsw G_ADD %0, %1, debug-location !12
+ $w0 = COPY %3(s32)
+ RET_ReallyLR implicit $w0
+ )";
+ auto TM = createTargetMachine(Triple::normalize("aarch64--"), "", "");
+ if (!TM)
+ return;
+ MachineModuleInfo MMI(TM.get());
+ std::unique_ptr<Module> M = parseMIR(*TM, MIR, MMI, &C);
+ ASSERT_TRUE(M);
+
+ DroppedVariableStatsMIR Stats;
+ auto *MF = MMI.getMachineFunction(*M->getFunction("_Z3fooi"));
+ Stats.runBeforePass("Test", MF);
+
+ // This loop simulates an IR pass that drops debug information.
+ for (auto &MBB : *MF) {
+ for (auto &MI : MBB) {
+ if (MI.isDebugValueLike()) {
+ MI.eraseFromParent();
+ break;
+ }
+ }
+ break;
+ }
+
+ Stats.runAfterPass("Test", MF);
+ ASSERT_EQ(Stats.getPassDroppedVariables(), true);
+}
+
+// This test ensures that if a DBG_VALUE is dropped after an optimization pass,
+// but an instruction that has a scope which is a child of the DBG_VALUE scope
+// still exists, and the DBG_VALUE is inlined at another location, debug
+// information is conisdered not dropped.
+TEST(DroppedVariableStatsMIR, InlinedAt) {
+ InitializeAllTargetInfos();
+ InitializeAllTargets();
+ InitializeAllTargetMCs();
+ PassInstrumentationCallbacks PIC;
+ PassInstrumentation PI(&PIC);
+
+ LLVMContext C;
+
+ const char *MIR =
+ R"(
+--- |
+ ; ModuleID = '/tmp/test.ll'
+ source_filename = "/tmp/test.ll"
+ target datalayout = "e-m:o-p270:32:32-p271:32:32-p272:64:64-i64:64-i128:128-n32:64-S128-Fn32"
+
+ define noundef range(i32 -2147483647, -2147483648) i32 @_Z3fooi(i32 noundef %x) local_unnamed_addr !dbg !4 {
+ entry:
+ #dbg_value(i32 %x, !10, !DIExpression(), !11)
+ %add = add nsw i32 %x, 1, !dbg !12
+ ret i32 0
+ }
+
+ !llvm.dbg.cu = !{!0}
+ !llvm.module.flags = !{!2}
+ !llvm.ident = !{!3}
+
+ !0 = distinct !DICompileUnit(language: DW_LANG_C_plus_plus_14, file: !1, producer: "clang", isOptimized: true, runtimeVersion: 0, emissionKind: FullDebug, splitDebugInlining: false, nameTableKind: Apple, sysroot: "/")
+ !1 = !DIFile(filename: "/tmp/code.cpp", directory: "/")
+ !2 = !{i32 2, !"Debug Info Version", i32 3}
+ !3 = !{!"clang"}
+ !4 = distinct !DISubprogram(name: "foo", linkageName: "_Z3fooi", scope: !5, file: !5, line: 1, type: !6, scopeLine: 1, spFlags: DISPFlagDefinition, unit: !0, retainedNodes: !9)
+ !5 = !DIFile(filename: "/tmp/code.cpp", directory: "")
+ !6 = !DISubroutineType(types: !7)
+ !7 = !{!8, !8}
+ !8 = !DIBasicType(name: "int", size: 32, encoding: DW_ATE_signed)
+ !9 = !{!10}
+ !10 = !DILocalVariable(name: "x", arg: 1, scope: !4, file: !5, line: 1, type: !8)
+ !11 = !DILocation(line: 0, scope: !4, inlinedAt: !14)
+ !12 = !DILocation(line: 2, column: 11, scope: !13)
+ !13 = distinct !DILexicalBlock(scope: !4, file: !5, line: 10, column: 28)
+ !14 = !DILocation(line: 3, column: 2, scope: !4)
+
+...
+---
+name: _Z3fooi
+alignment: 4
+exposesReturnsTwice: false
+legalized: false
+regBankSelected: false
+selected: false
+failedISel: false
+tracksRegLiveness: true
+hasWinCFI: false
+noPhis: false
+isSSA: true
+noVRegs: false
+hasFakeUses: false
+callsEHReturn: false
+callsUnwindInit: false
+hasEHCatchret: false
+hasEHScopes: false
+hasEHFunclets: false
+isOutlined: false
+debugInstrRef: false
+failsVerification: false
+tracksDebugUserValues: false
+registers:
+ - { id: 0, class: _, preferred-register: '', flags: [ ] }
+ - { id: 1, class: _, preferred-register: '', flags: [ ] }
+ - { id: 2, class: _, preferred-register: '', flags: [ ] }
+ - { id: 3, class: _, preferred-register: '', flags: [ ] }
+liveins:
+ - { reg: '$w0', virtual-reg: '' }
+frameInfo:
+ isFrameAddressTaken: false
+ isReturnAddressTaken: false
+ hasStackMap: false
+ hasPatchPoint: false
+ stackSize: 0
+ offsetAdjustment: 0
+ maxAlignment: 1
+ adjustsStack: false
+ hasCalls: false
+ stackProtector: ''
+ functionContext: ''
+ maxCallFrameSize: 4294967295
+ cvBytesOfCalleeSavedRegisters: 0
+ hasOpaqueSPAdjustment: false
+ hasVAStart: false
+ hasMustTailInVarArgFunc: false
+ hasTailCall: false
+ isCalleeSavedInfoValid: false
+ localFrameSize: 0
+ savePoint: ''
+ restorePoint: ''
+fixedStack: []
+stack: []
+entry_values: []
+callSites: []
+debugValueSubstitutions: []
+constants: []
+machineFunctionInfo: {}
+body: |
+ bb.1.entry:
+ liveins: $w0
+
+ %0:_(s32) = COPY $w0
+ %1:_(s32) = G_CONSTANT i32 1
+ %3:_(s32) = G_CONSTANT i32 0
+ DBG_VALUE %0(s32), $noreg, !10, !DIExpression(), debug-location !11
+ %2:_(s32) = nsw G_ADD %0, %1, debug-location !12
+ $w0 = COPY %3(s32)
+ RET_ReallyLR implicit $w0
+ )";
+ auto TM = createTargetMachine(Triple::normalize("aarch64--"), "", "");
+ if (!TM)
+ return;
+ MachineModuleInfo MMI(TM.get());
+ std::unique_ptr<Module> M = parseMIR(*TM, MIR, MMI, &C);
+ ASSERT_TRUE(M);
+
+ DroppedVariableStatsMIR Stats;
+ auto *MF = MMI.getMachineFunction(*M->getFunction("_Z3fooi"));
+ Stats.runBeforePass("Test", MF);
+
+ // This loop simulates an IR pass that drops debug information.
+ for (auto &MBB : *MF) {
+ for (auto &MI : MBB) {
+ if (MI.isDebugValueLike()) {
+ MI.eraseFromParent();
+ break;
+ }
+ }
+ break;
+ }
+
+ Stats.runAfterPass("Test", MF);
+ ASSERT_EQ(Stats.getPassDroppedVariables(), false);
+}
+
+// This test ensures that if a DBG_VALUE is dropped after an optimization pass,
+// but an instruction that has a scope which is a child of the DBG_VALUE scope
+// still exists, and the DBG_VALUE and the instruction are inlined at another
+// location, debug information is conisdered dropped.
+TEST(DroppedVariableStatsMIR, InlinedAtShared) {
+ InitializeAllTargetInfos();
+ InitializeAllTargets();
+ InitializeAllTargetMCs();
+ PassInstrumentationCallbacks PIC;
+ PassInstrumentation PI(&PIC);
+
+ LLVMContext C;
+
+ const char *MIR =
+ R"(
+--- |
+ ; ModuleID = '/tmp/test.ll'
+ source_filename = "/tmp/test.ll"
+ target datalayout = "e-m:o-p270:32:32-p271:32:32-p272:64:64-i64:64-i128:128-n32:64-S128-Fn32"
+
+ define noundef range(i32 -2147483647, -2147483648) i32 @_Z3fooi(i32 noundef %x) local_unnamed_addr !dbg !4 {
+ entry:
+ #dbg_value(i32 %x, !10, !DIExpression(), !11)
+ %add = add nsw i32 %x, 1, !dbg !12
+ ret i32 0
+ }
+
+ !llvm.dbg.cu = !{!0}
+ !llvm.module.flags = !{!2}
+ !llvm.ident = !{!3}
+
+ !0 = distinct !DICompileUnit(language: DW_LANG_C_plus_plus_14, file: !1, producer: "clang", isOptimized: true, runtimeVersion: 0, emissionKind: FullDebug, splitDebugInlining: false, nameTableKind: Apple, sysroot: "/")
+ !1 = !DIFile(filename: "/tmp/code.cpp", directory: "/")
+ !2 = !{i32 2, !"Debug Info Version", i32 3}
+ !3 = !{!"clang"}
+ !4 = distinct !DISubprogram(name: "foo", linkageName: "_Z3fooi", scope: !5, file: !5, line: 1, type: !6, scopeLine: 1, spFlags: DISPFlagDefinition, unit: !0, retainedNodes: !9)
+ !5 = !DIFile(filename: "/tmp/code.cpp", directory: "")
+ !6 = !DISubroutineType(types: !7)
+ !7 = !{!8, !8}
+ !8 = !DIBasicType(name: "int", size: 32, encoding: DW_ATE_signed)
+ !9 = !{!10}
+ !10 = !DILocalVariable(name: "x", arg: 1, scope: !4, file: !5, line: 1, type: !8)
+ !11 = !DILocation(line: 0, scope: !4, inlinedAt: !14)
+ !12 = !DILocation(line: 2, column: 11, scope: !13, inlinedAt: !14)
+ !13 = distinct !DILexicalBlock(scope: !4, file: !5, line: 10, column: 28)
+ !14 = !DILocation(line: 3, column: 2, scope: !4)
+
+...
+---
+name: _Z3fooi
+alignment: 4
+exposesReturnsTwice: false
+legalized: false
+regBankSelected: false
+selected: false
+failedISel: false
+tracksRegLiveness: true
+hasWinCFI: false
+noPhis: false
+isSSA: true
+noVRegs: false
+hasFakeUses: false
+callsEHReturn: false
+callsUnwindInit: false
+hasEHCatchret: false
+hasEHScopes: false
+hasEHFunclets: false
+isOutlined: false
+debugInstrRef: false
+failsVerification: false
+tracksDebugUserValues: false
+registers:
+ - { id: 0, class: _, preferred-register: '', flags: [ ] }
+ - { id: 1, class: _, preferred-register: '', flags: [ ] }
+ - { id: 2, class: _, preferred-register: '', flags: [ ] }
+ - { id: 3, class: _, preferred-register: '', flags: [ ] }
+liveins:
+ - { reg: '$w0', virtual-reg: '' }
+frameInfo:
+ isFrameAddressTaken: false
+ isReturnAddressTaken: false
+ hasStackMap: false
+ hasPatchPoint: false
+ stackSize: 0
+ offsetAdjustment: 0
+ maxAlignment: 1
+ adjustsStack: false
+ hasCalls: false
+ stackProtector: ''
+ functionContext: ''
+ maxCallFrameSize: 4294967295
+ cvBytesOfCalleeSavedRegisters: 0
+ hasOpaqueSPAdjustment: false
+ hasVAStart: false
+ hasMustTailInVarArgFunc: false
+ hasTailCall: false
+ isCalleeSavedInfoValid: false
+ localFrameSize: 0
+ savePoint: ''
+ restorePoint: ''
+fixedStack: []
+stack: []
+entry_values: []
+callSites: []
+debugValueSubstitutions: []
+constants: []
+machineFunctionInfo: {}
+body: |
+ bb.1.entry:
+ liveins: $w0
+
+ %0:_(s32) = COPY $w0
+ %1:_(s32) = G_CONSTANT i32 1
+ %3:_(s32) = G_CONSTANT i32 0
+ DBG_VALUE %0(s32), $noreg, !10, !DIExpression(), debug-location !11
+ %2:_(s32) = nsw G_ADD %0, %1, debug-location !12
+ $w0 = COPY %3(s32)
+ RET_ReallyLR implicit $w0
+ )";
+ auto TM = createTargetMachine(Triple::normalize("aarch64--"), "", "");
+ if (!TM)
+ return;
+ MachineModuleInfo MMI(TM.get());
+ std::unique_ptr<Module> M = parseMIR(*TM, MIR, MMI, &C);
+ ASSERT_TRUE(M);
+
+ DroppedVariableStatsMIR Stats;
+ auto *MF = MMI.getMachineFunction(*M->getFunction("_Z3fooi"));
+ Stats.runBeforePass("Test", MF);
+
+ // This loop simulates an IR pass that drops debug information.
+ for (auto &MBB : *MF) {
+ for (auto &MI : MBB) {
+ if (MI.isDebugValueLike()) {
+ MI.eraseFromParent();
+ break;
+ }
+ }
+ break;
+ }
+
+ Stats.runAfterPass("Test", MF);
+ ASSERT_EQ(Stats.getPassDroppedVariables(), true);
+}
+
+// This test ensures that if a DBG_VALUE is dropped after an optimization pass,
+// but an instruction that has a scope which is a child of the DBG_VALUE scope
+// still exists, and the instruction is inlined at a location that is the
+// DBG_VALUE's inlined at location, debug information is conisdered dropped.
+TEST(DroppedVariableStatsMIR, InlinedAtChild) {
+ InitializeAllTargetInfos();
+ InitializeAllTargets();
+ InitializeAllTargetMCs();
+ PassInstrumentationCallbacks PIC;
+ PassInstrumentation PI(&PIC);
+
+ LLVMContext C;
+
+ const char *MIR =
+ R"(
+--- |
+ ; ModuleID = '/tmp/test.ll'
+ source_filename = "/tmp/test.ll"
+ target datalayout = "e-m:o-p270:32:32-p271:32:32-p272:64:64-i64:64-i128:128-n32:64-S128-Fn32"
+
+ define noundef range(i32 -2147483647, -2147483648) i32 @_Z3fooi(i32 noundef %x) local_unnamed_addr !dbg !4 {
+ entry:
+ #dbg_value(i32 %x, !10, !DIExpression(), !11)
+ %add = add nsw i32 %x, 1, !dbg !12
+ ret i32 0
+ }
+
+ !llvm.dbg.cu = !{!0}
+ !llvm.module.flags = !{!2}
+ !llvm.ident = !{!3}
+
+ !0 = distinct !DICompileUnit(language: DW_LANG_C_plus_plus_14, file: !1, producer: "clang", isOptimized: true, runtimeVersion: 0, emissionKind: FullDebug, splitDebugInlining: false, nameTableKind: Apple, sysroot: "/")
+ !1 = !DIFile(filename: "/tmp/code.cpp", directory: "/")
+ !2 = !{i32 2, !"Debug Info Version", i32 3}
+ !3 = !{!"clang"}
+ !4 = distinct !DISubprogram(name: "foo", linkageName: "_Z3fooi", scope: !5, file: !5, line: 1, type: !6, scopeLine: 1, spFlags: DISPFlagDefinition, unit: !0, retainedNodes: !9)
+ !5 = !DIFile(filename: "/tmp/code.cpp", directory: "")
+ !6 = !DISubroutineType(types: !7)
+ !7 = !{!8, !8}
+ !8 = !DIBasicType(name: "int", size: 32, encoding: DW_ATE_signed)
+ !9 = !{!10}
+ !10 = !DILocalVariable(name: "x", arg: 1, scope: !4, file: !5, line: 1, type: !8)
+ !11 = !DILocation(line: 0, scope: !4, inlinedAt: !14)
+ !12 = !DILocation(line: 2, column: 11, scope: !13, inlinedAt: !15)
+ !13 = distinct !DILexicalBlock(scope: !4, file: !5, line: 10, column: 28)
+ !14 = !DILocation(line: 3, column: 2, scope: !4)
+ !15 = !DILocation(line: 4, column: 5, scope: !13, inlinedAt: !14)
+
+...
+---
+name: _Z3fooi
+alignment: 4
+exposesReturnsTwice: false
+legalized: false
+regBankSelected: false
+selected: false
+failedISel: false
+tracksRegLiveness: true
+hasWinCFI: false
+noPhis: false
+isSSA: true
+noVRegs: false
+hasFakeUses: false
+callsEHReturn: false
+callsUnwindInit: false
+hasEHCatchret: false
+hasEHScopes: false
+hasEHFunclets: false
+isOutlined: false
+debugInstrRef: false
+failsVerification: false
+tracksDebugUserValues: false
+registers:
+ - { id: 0, class: _, preferred-register: '', flags: [ ] }
+ - { id: 1, class: _, preferred-register: '', flags: [ ] }
+ - { id: 2, class: _, preferred-register: '', flags: [ ] }
+ - { id: 3, class: _, preferred-register: '', flags: [ ] }
+liveins:
+ - { reg: '$w0', virtual-reg: '' }
+frameInfo:
+ isFrameAddressTaken: false
+ isReturnAddressTaken: false
+ hasStackMap: false
+ hasPatchPoint: false
+ stackSize: 0
+ offsetAdjustment: 0
+ maxAlignment: 1
+ adjustsStack: false
+ hasCalls: false
+ stackProtector: ''
+ functionContext: ''
+ maxCallFrameSize: 4294967295
+ cvBytesOfCalleeSavedRegisters: 0
+ hasOpaqueSPAdjustment: false
+ hasVAStart: false
+ hasMustTailInVarArgFunc: false
+ hasTailCall: false
+ isCalleeSavedInfoValid: false
+ localFrameSize: 0
+ savePoint: ''
+ restorePoint: ''
+fixedStack: []
+stack: []
+entry_values: []
+callSites: []
+debugValueSubstitutions: []
+constants: []
+machineFunctionInfo: {}
+body: |
+ bb.1.entry:
+ liveins: $w0
+
+ %0:_(s32) = COPY $w0
+ %1:_(s32) = G_CONSTANT i32 1
+ %3:_(s32) = G_CONSTANT i32 0
+ DBG_VALUE %0(s32), $noreg, !10, !DIExpression(), debug-location !11
+ %2:_(s32) = nsw G_ADD %0, %1, debug-location !12
+ $w0 = COPY %3(s32)
+ RET_ReallyLR implicit $w0
+ )";
+ auto TM = createTargetMachine(Triple::normalize("aarch64--"), "", "");
+ if (!TM)
+ return;
+ MachineModuleInfo MMI(TM.get());
+ std::unique_ptr<Module> M = parseMIR(*TM, MIR, MMI, &C);
+ ASSERT_TRUE(M);
+
+ DroppedVariableStatsMIR Stats;
+ auto *MF = MMI.getMachineFunction(*M->getFunction("_Z3fooi"));
+ Stats.runBeforePass("Test", MF);
+
+ // This loop simulates an IR pass that drops debug information.
+ for (auto &MBB : *MF) {
+ for (auto &MI : MBB) {
+ if (MI.isDebugValueLike()) {
+ MI.eraseFromParent();
+ break;
+ }
+ }
+ break;
+ }
+
+ Stats.runAfterPass("Test", MF);
+ ASSERT_EQ(Stats.getPassDroppedVariables(), true);
+}
+
+} // end anonymous namespace
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