diff --git a/llvm/docs/BugpointRedesign.md b/llvm/docs/BugpointRedesign.md
new file mode 100644
--- /dev/null
+++ b/llvm/docs/BugpointRedesign.md
@@ -0,0 +1,105 @@
+# Bugpoint Redesign
+Author: Diego Treviño (diegotf@google.com)
+
+Date: 2019-06-05
+
+Status: Draft
+
+
+## Introduction
+As use of bugpoint has grown several areas of improvement have been identified
+through years of use: confusing to use, slow, it doesn’t always produce high
+quality test cases, etc. This document proposes a new approach with a narrower
+focus: minimization of IR test cases.
+
+
+## Proposed New Design
+
+
+### Narrow focus: test-case reduction
+The main focus will be a code reduction strategy to obtain much smaller test
+cases that still have the same property as the original one. This will be done
+via classic delta debugging and by adding some IR-specific reductions (e.g.
+replacing globals, removing unused instructions, etc), similar to what
+already exists, but with more in-depth minimization.
+
+
+Granted, if the community differs on this proposal, the legacy code could still
+be present in the tool, but with the caveat of still being documented and
+designed towards delta reduction.
+
+
+### Command-Line Options
+We are proposing to reduce the plethora of bugpoint’s options to just two: an
+interesting-ness test and the arguments for said test, similar to other delta
+reduction tools such as CReduce, Delta, and Lithium; the tool should feel less
+ cluttered, and there should also be no uncertainty about how to operate it.
+
+
+The interesting-ness test that’s going to be run to reduce the code is given
+by name:
+ `--test=<test_name>`
+If a `--test` option is not given, the program exits; this option is similar
+to bugpoint’s current `-compile-custom` option, which lets the user run a
+custom script.
+
+
+The interesting-ness test would be defined as a script that returns 0 when the
+IR achieves a user-defined behaviour (e.g. failure to compile on clang) and a
+nonzero value when otherwise. Leaving the user the freedom to determine what is
+and isn’t interesting to the tool, and thus, streamlining the process of
+reducing a test-case.
+
+
+If the test accepts any arguments (excluding the input ll/bc file), they are
+given via the following flag:
+ `--test_args=<test_arguments>`
+If unspecified, the test is run as given. It’s worth noting that the input file
+would be passed as a parameter to the test, similar how `-compile-custom`
+currently operates.
+
+
+### Implementation
+The tool would behave similar to CReduce’s functionality in that it would have a
+list of passes that try to minimize the given test-case. We should be able to
+modularize the tool’s behavior, as well as making it easier to maintain and
+expand.
+
+
+The first version of this redesign would try to:
+
+
+* Discard functions, instructions and metadata that don’t influence the
+ interesting-ness test
+* Remove unused parameters from functions
+* Eliminate unvisited conditional paths
+* Rename variables to more regular ones (such as “aâ€, “bâ€, “câ€, etc.)
+
+
+Once these passes are implemented, more meaningful reductions (such as type
+reduction) would be added to the tool, to even further reduce IR.
+
+
+## Background on historical bugpoint issues
+
+
+### Root Cause Analysis
+Presently, bugpoint takes a long time to find the source problem in a given IR
+file, mainly due to the fact that it tries to debug the input by running
+various strategies to classify the bug, which in turn run multiple optimizer
+and compilation passes over the input, taking up a lot of time. Furthermore,
+when the IR crashes, it tries to reduce it by performing some sub-optimal
+passes (e.g. a lot of unreachable blocks), and sometimes even fails to minimize
+at all.
+
+
+### "Quirky" Interface
+Bugpoint’s current interface overwhelms and confuses the user, the help screen
+alone ends up confusing rather providing guidance, as seen below:
+
+
+
+And, not only are there numerous features and options, but some of them also
+work in unexpected ways and most of the time the user ends up using a custom
+script. Pruning and simplifying the interface will be worth considering in
+order to make the tool more useful in the general case and easier to maintain.
diff --git a/llvm/test/Reduce/Inputs/remove-funcs.sh b/llvm/test/Reduce/Inputs/remove-funcs.sh
new file mode 100755
--- /dev/null
+++ b/llvm/test/Reduce/Inputs/remove-funcs.sh
@@ -0,0 +1,10 @@
+#!/bin/sh
+set -e
+
+matches=$(cat $1 | grep "@interesting" | wc -l)
+
+if [[ $matches > 0 ]]; then
+ exit 0
+else
+ exit 1
+fi
diff --git a/llvm/test/Reduce/remove-funcs.ll b/llvm/test/Reduce/remove-funcs.ll
new file mode 100644
--- /dev/null
+++ b/llvm/test/Reduce/remove-funcs.ll
@@ -0,0 +1,34 @@
+; Test that llvm-reduce can remove uninteresting functions as well as
+; their InstCalls.
+;
+; RUN: llvm-reduce --test %p/Inputs/remove-funcs.sh %s
+; RUN: cat reduced.ll | FileCheck %s
+; REQUIRES: plugins, shell
+
+; CHECK-NOT: uninteresting1()
+define i32 @uninteresting1() {
+entry:
+ ret i32 0
+}
+
+; CHECK: interesting()
+define i32 @interesting() {
+entry:
+ ; CHECK: call i32 @interesting()
+ %call2 = call i32 @interesting()
+ ; CHECK-NOT: call i32 @uninteresting1()
+ %call = call i32 @uninteresting1()
+ ret i32 5
+}
+
+; CHECK-NOT: uninteresting2()
+define i32 @uninteresting2() {
+entry:
+ ret i32 0
+}
+
+; CHECK-NOT: uninteresting3()
+define i32 @uninteresting3() {
+entry:
+ ret i32 10
+}
diff --git a/llvm/tools/LLVMBuild.txt b/llvm/tools/LLVMBuild.txt
--- a/llvm/tools/LLVMBuild.txt
+++ b/llvm/tools/LLVMBuild.txt
@@ -48,6 +48,7 @@
llvm-pdbutil
llvm-profdata
llvm-rc
+ llvm-reduce
llvm-rtdyld
llvm-size
llvm-split
diff --git a/llvm/tools/llvm-reduce/CMakeLists.txt b/llvm/tools/llvm-reduce/CMakeLists.txt
new file mode 100644
--- /dev/null
+++ b/llvm/tools/llvm-reduce/CMakeLists.txt
@@ -0,0 +1,24 @@
+set(LLVM_LINK_COMPONENTS
+ AllTargetsAsmParsers
+ AllTargetsCodeGens
+ AllTargetsDescs
+ AllTargetsInfos
+ IRReader
+ Support
+ Target
+ TransformUtils
+ )
+
+# Support plugins.
+set(LLVM_NO_DEAD_STRIP 1)
+
+add_llvm_tool(llvm-reduce
+ llvm-reduce.cpp
+ TestRunner.cpp
+ deltas/Delta.cpp
+ deltas/ReduceFunctions.cpp
+
+ DEPENDS
+ intrinsics_gen
+ )
+export_executable_symbols(llvm-reduce)
diff --git a/llvm/tools/llvm-reduce/DeltaManager.h b/llvm/tools/llvm-reduce/DeltaManager.h
new file mode 100644
--- /dev/null
+++ b/llvm/tools/llvm-reduce/DeltaManager.h
@@ -0,0 +1,25 @@
+//===- DeltaManager.h - Runs Delta Passes to reduce Input -----------------===//
+//
+// 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
+//
+//===----------------------------------------------------------------------===//
+//
+// This file calls each specialized Delta pass in order to reduce the input IR
+// file.
+//
+//===----------------------------------------------------------------------===//
+
+#include "TestRunner.h"
+#include "deltas/Delta.h"
+#include "deltas/ReduceFunctions.h"
+
+namespace llvm {
+
+inline void runDeltaPasses(TestRunner &Tester) {
+ reduceFunctionsDeltaPass(Tester);
+ // TODO: Implement the remaining Delta Passes
+}
+
+} // namespace llvm
diff --git a/llvm/tools/LLVMBuild.txt b/llvm/tools/llvm-reduce/LLVMBuild.txt
copy from llvm/tools/LLVMBuild.txt
copy to llvm/tools/llvm-reduce/LLVMBuild.txt
--- a/llvm/tools/LLVMBuild.txt
+++ b/llvm/tools/llvm-reduce/LLVMBuild.txt
@@ -1,4 +1,4 @@
-;===- ./tools/LLVMBuild.txt ------------------------------------*- Conf -*--===;
+;===- ./tools/llvm-reduce/LLVMBuild.txt ------------------------*- Conf -*--===;
;
; Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
; See https://llvm.org/LICENSE.txt for license information.
@@ -14,48 +14,11 @@
;
;===------------------------------------------------------------------------===;
-[common]
-subdirectories =
- bugpoint
- dsymutil
- llc
- lli
- llvm-ar
- llvm-as
- llvm-bcanalyzer
- llvm-cat
- llvm-cfi-verify
- llvm-cov
- llvm-cvtres
- llvm-diff
- llvm-dis
- llvm-dwarfdump
- llvm-dwp
- llvm-elfabi
- llvm-exegesis
- llvm-extract
- llvm-jitlistener
- llvm-jitlink
- llvm-link
- llvm-lto
- llvm-mc
- llvm-mca
- llvm-modextract
- llvm-mt
- llvm-nm
- llvm-objcopy
- llvm-objdump
- llvm-pdbutil
- llvm-profdata
- llvm-rc
- llvm-rtdyld
- llvm-size
- llvm-split
- llvm-undname
- opt
- verify-uselistorder
-
[component_0]
-type = Group
-name = Tools
-parent = $ROOT
+type = Tool
+name = llvm-reduce
+parent = Tools
+required_libraries =
+ BitReader
+ IRReader
+ all-targets
diff --git a/llvm/tools/llvm-reduce/TestRunner.h b/llvm/tools/llvm-reduce/TestRunner.h
new file mode 100644
--- /dev/null
+++ b/llvm/tools/llvm-reduce/TestRunner.h
@@ -0,0 +1,56 @@
+//===-- tools/llvm-reduce/TestRunner.h ---------------------------*- 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
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef LLVM_TOOLS_LLVMREDUCE_TESTRUNNER_H
+#define LLVM_TOOLS_LLVMREDUCE_TESTRUNNER_H
+
+#include "llvm/ADT/SmallString.h"
+#include "llvm/IR/Module.h"
+#include "llvm/Support/Error.h"
+#include "llvm/Support/FileSystem.h"
+#include "llvm/Support/Path.h"
+#include "llvm/Support/Program.h"
+#include <vector>
+
+namespace llvm {
+
+// This class contains all the info necessary for running the provided
+// interesting-ness test, as well as the most reduced module and its
+// respective filename.
+class TestRunner {
+public:
+ TestRunner(StringRef TestName, std::vector<std::string> TestArgs,
+ StringRef ReducedFilepath);
+
+ /// Runs the interesting-ness test for the specified file
+ /// @returns 0 if test was successful, 1 if otherwise
+ int run(StringRef Filename);
+
+ /// Filename to the most reduced testcase
+ StringRef getReducedFilepath() const { return ReducedFilepath; }
+ /// Directory where tmp files are created
+ StringRef getTmpDir() const { return TmpDirectory; }
+ /// Returns the most reduced version of the original testcase
+ Module *getProgram() const { return Program.get(); }
+
+ void setReducedFilepath(SmallString<128> F) {
+ ReducedFilepath = std::move(F);
+ }
+ void setProgram(std::unique_ptr<Module> P) { Program = std::move(P); }
+
+private:
+ SmallString<128> TestName;
+ std::vector<std::string> TestArgs;
+ SmallString<128> ReducedFilepath;
+ SmallString<128> TmpDirectory;
+ std::unique_ptr<Module> Program;
+};
+
+} // namespace llvm
+
+#endif
diff --git a/llvm/tools/llvm-reduce/TestRunner.cpp b/llvm/tools/llvm-reduce/TestRunner.cpp
new file mode 100644
--- /dev/null
+++ b/llvm/tools/llvm-reduce/TestRunner.cpp
@@ -0,0 +1,60 @@
+//===-- TestRunner.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 "TestRunner.h"
+#include <utility>
+
+using namespace llvm;
+
+/// Gets Current Working Directory and tries to create a Tmp Directory
+static SmallString<128> initializeTmpDirectory() {
+ SmallString<128> CWD;
+ if (std::error_code EC = sys::fs::current_path(CWD)) {
+ errs() << "Error getting current directory: " << EC.message() << "!\n";
+ exit(1);
+ }
+
+ SmallString<128> TmpDirectory;
+ sys::path::append(TmpDirectory, CWD, "tmp");
+ if (std::error_code EC = sys::fs::create_directory(TmpDirectory))
+ errs() << "Error creating tmp directory: " << EC.message() << "!\n";
+
+ return TmpDirectory;
+}
+
+TestRunner::TestRunner(StringRef TestName, std::vector<std::string> TestArgs,
+ StringRef ReducedFilepath)
+ : TestName(TestName), TestArgs(std::move(TestArgs)),
+ ReducedFilepath(ReducedFilepath) {
+ TmpDirectory = initializeTmpDirectory();
+}
+
+/// Runs the interestingness test, passes file to be tested as first argument
+/// and other specified test arguments after that.
+int TestRunner::run(StringRef Filename) {
+ std::vector<StringRef> ProgramArgs;
+ ProgramArgs.push_back(TestName);
+ ProgramArgs.push_back(Filename);
+
+ for (auto Arg : TestArgs)
+ ProgramArgs.push_back(Arg.c_str());
+ for (unsigned I = 0, E = ProgramArgs.size(); I != E; ++I)
+ outs() << ProgramArgs[I] << "\n";
+ StringRef SR = "";
+ Optional<StringRef> Redirects[3] = {SR, SR, SR}; // STDIN, STDOUT, STDERR
+ int Result = sys::ExecuteAndWait(TestName, ProgramArgs, None, Redirects);
+
+ if (Result < 0) {
+ Error E = make_error<StringError>("Error running interesting-ness test\n",
+ inconvertibleErrorCode());
+ outs() << toString(std::move(E));
+ exit(1);
+ }
+
+ return !Result;
+}
diff --git a/llvm/tools/llvm-reduce/deltas/Delta.h b/llvm/tools/llvm-reduce/deltas/Delta.h
new file mode 100644
--- /dev/null
+++ b/llvm/tools/llvm-reduce/deltas/Delta.h
@@ -0,0 +1,89 @@
+//===- Delta.h - Delta Debugging Algorithm Implementation -----------------===//
+//
+// 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
+//
+//===----------------------------------------------------------------------===//
+//
+// This file contains the implementation for the Delta Debugging Algorithm:
+// it splits a given set of Targets (i.e. Functions, Instructions, BBs, etc.)
+// into chunks and tries to reduce the number chunks that are interesting.
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef LLVM_TOOLS_LLVMREDUCE_LLVMREDUCE_DELTA_H
+#define LLVM_TOOLS_LLVMREDUCE_LLVMREDUCE_DELTA_H
+
+#include "../TestRunner.h"
+#include "llvm/IR/Verifier.h"
+#include "llvm/Support/FileSystem.h"
+#include "llvm/Support/Path.h"
+#include "llvm/Support/ScopedPrinter.h"
+#include "llvm/Support/ToolOutputFile.h"
+#include "llvm/Transforms/Utils/Cloning.h"
+#include <fstream>
+#include <set>
+#include <vector>
+
+using namespace llvm;
+
+struct Chunk {
+ unsigned begin;
+ unsigned end;
+
+ /// Helper function to verify if a given Target-index is inside the Chunk
+ bool contains(unsigned Index) const { return Index >= begin && Index <= end; }
+
+ void print() const {
+ outs() << "[" << begin;
+ if (end - begin != 0)
+ outs() << "," << end;
+ outs() << "]";
+ }
+
+ /// Operator when populating CurrentChunks in Generic Delta Pass
+ friend bool operator!=(const Chunk &C1, const Chunk &C2) {
+ return C1.begin != C2.begin || C1.end != C2.end;
+ }
+
+ /// Operator used for sets
+ friend bool operator<(const Chunk &C1, const Chunk &C2) {
+ return std::tie(C1.begin, C1.end) < std::tie(C2.begin, C2.end);
+ }
+};
+
+namespace llvm {
+
+/// This function implements the Delta Debugging algorithm, it receives a
+/// number of Targets (e.g. Functions, Instructions, Basic Blocks, etc.) and
+/// splits them in half; these chunks of targets are then tested while ignoring
+/// one chunk, if a chunk is proven to be uninteresting (i.e. fails the test)
+/// it is removed from consideration. The algorithm will attempt to split the
+/// Chunks in half and start the process again until it can't split chunks
+/// anymore.
+///
+/// This function is intended to be called by each specialized delta pass (e.g.
+/// RemoveFunctions) and receives three key parameters:
+/// * Test: The main TestRunner instance which is used to run the provided
+/// interesting-ness test, as well as to store and access the reduced Program.
+/// * Targets: The amount of Targets that are going to be reduced by the
+/// algorithm, for example, the RemoveGlobalVars pass would send the amount of
+/// initialized GVs.
+/// * ExtractChunksFromModule: A function used to tailor the main program so it
+/// only contains Targets that are inside Chunks of the given iteration.
+/// Note: This function is implemented by each specialized Delta pass
+///
+/// Other implementations of the Delta Debugging algorithm can also be found in
+/// the CReduce, Delta, and Lithium projects.
+void runDeltaPass(TestRunner &Test, unsigned Targets,
+ std::function<void(const std::vector<Chunk> &, Module *)>
+ ExtractChunksFromModule);
+
+bool runTestWithoutChunks(
+ TestRunner &Test, std::function<void(const std::vector<Chunk> &, Module *)>
+ ExtractChunksFromModule);
+
+} // namespace llvm
+
+#endif
diff --git a/llvm/tools/llvm-reduce/deltas/Delta.cpp b/llvm/tools/llvm-reduce/deltas/Delta.cpp
new file mode 100644
--- /dev/null
+++ b/llvm/tools/llvm-reduce/deltas/Delta.cpp
@@ -0,0 +1,203 @@
+//===- Delta.cpp - Delta Debugging Algorithm Implementation ---------------===//
+//
+// 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
+//
+//===----------------------------------------------------------------------===//
+//
+// This file contains the implementation for the Delta Debugging Algorithm:
+// it splits a given set of Targets (i.e. Functions, Instructions, BBs, etc.)
+// into chunks and tries to reduce the number chunks that are interesting.
+//
+//===----------------------------------------------------------------------===//
+
+#include "Delta.h"
+#include "llvm/Transforms/Utils/Cloning.h"
+
+/// Writes IR code to the given Filepath
+static bool writeProgramToFile(StringRef Filepath, int FD, const Module &M) {
+ ToolOutputFile Out(Filepath, FD);
+ M.print(Out.os(), /*AnnotationWriter=*/nullptr);
+ Out.os().close();
+
+ if (!Out.os().has_error()) {
+ Out.keep();
+ return false;
+ }
+ return true;
+}
+
+/// Creates a temporary (and unique) file inside the tmp folder and writes
+/// the given module IR.
+static SmallString<128> createTmpFile(Module *M, StringRef TmpDir) {
+ SmallString<128> UniqueFilepath;
+ int UniqueFD;
+
+ std::error_code EC = sys::fs::createUniqueFile(TmpDir + "/tmp-%%%.ll",
+ UniqueFD, UniqueFilepath);
+ if (EC) {
+ errs() << "Error making unique filename: " << EC.message() << "!\n";
+ exit(1);
+ }
+
+ if (writeProgramToFile(UniqueFilepath, UniqueFD, *M)) {
+ errs() << "Error emitting bitcode to file '" << UniqueFilepath << "'!\n";
+ exit(1);
+ }
+ return UniqueFilepath;
+}
+
+/// Prints the Chunk Indexes with the following format: [start, end], if
+/// chunk is at minimum size (1), then it just displays [start].
+static void printChunks(std::vector<Chunk> Chunks, bool Oneline = false) {
+ if (Chunks.empty()) {
+ outs() << "No Chunks";
+ return;
+ }
+
+ for (auto C : Chunks) {
+ if (!Oneline)
+ outs() << '\t';
+ C.print();
+ if (!Oneline)
+ outs() << '\n';
+ }
+}
+
+/// Counts the amount of lines for a given file
+static unsigned getLines(StringRef Filepath) {
+ unsigned Lines = 0;
+ std::string CurrLine;
+ std::ifstream FileStream(Filepath);
+
+ while (std::getline(FileStream, CurrLine))
+ ++Lines;
+
+ return Lines;
+}
+
+/// Splits Chunks in half and prints them.
+/// If unable to split (when chunk size is 1) returns false.
+static bool increaseGranularity(std::vector<Chunk> &Chunks) {
+ outs() << "Increasing granularity...";
+ std::vector<Chunk> NewChunks;
+ bool SplitOne = false;
+
+ for (auto &C : Chunks) {
+ if (C.end - C.begin == 0)
+ NewChunks.push_back(C);
+ else {
+ unsigned Half = (C.begin + C.end) / 2;
+ NewChunks.push_back({C.begin, Half});
+ NewChunks.push_back({Half + 1, C.end});
+ SplitOne = true;
+ }
+ }
+ if (SplitOne) {
+ Chunks = NewChunks;
+ outs() << "Success! New Chunks:\n";
+ printChunks(Chunks);
+ }
+ return SplitOne;
+}
+
+bool llvm::runTestWithoutChunks(
+ TestRunner &Test, std::function<void(const std::vector<Chunk> &, Module *)>
+ ExtractChunksFromModule) {
+ std::unique_ptr<Module> Clone = CloneModule(*Test.getProgram());
+
+ // Generate Module with only Targets inside Current Chunks
+ ExtractChunksFromModule({}, Clone.get());
+ // Write Module to tmp file
+ SmallString<128> CurrentFilepath =
+ createTmpFile(Clone.get(), Test.getTmpDir());
+ outs() << " | " << sys::path::filename(CurrentFilepath);
+
+ // Completely reduced Program isn't interesting
+ if (!Test.run(CurrentFilepath))
+ return false;
+
+ // Hooray! We reduced the testcase completely
+ Test.setReducedFilepath(CurrentFilepath);
+ Test.setProgram(std::move(Clone));
+ return true;
+}
+
+/// Runs the Delta Debugging algorithm, splits the code into chunks and
+/// reduces the amount of chunks that are considered interesting by the
+/// given test.
+void llvm::runDeltaPass(
+ TestRunner &Test, unsigned Targets,
+ std::function<void(const std::vector<Chunk> &, Module *)>
+ ExtractChunksFromModule) {
+ if (!Targets)
+ return;
+
+ std::vector<Chunk> Chunks = {{1, Targets}};
+ std::set<Chunk> UninterestingChunks;
+ std::unique_ptr<Module> ReducedProgram;
+
+ if (!Test.run(Test.getReducedFilepath())) {
+ outs() << "\nInput isn't interesting! Verify interesting-ness test\n";
+ outs() << "----------------------------\n";
+ return;
+ }
+
+ if (!increaseGranularity(Chunks)) {
+ outs() << "\nCan't reduce anymore\n";
+ outs() << "----------------------------\n";
+ return;
+ }
+
+ do {
+ UninterestingChunks = {};
+ for (int I = Chunks.size() - 1; I >= 0; --I) {
+ std::vector<Chunk> CurrentChunks;
+
+ for (auto C : Chunks)
+ if (!UninterestingChunks.count(C) && C != Chunks[I])
+ CurrentChunks.push_back(C);
+
+ if (CurrentChunks.empty())
+ continue;
+
+ // Clone module before hacking it up..
+ std::unique_ptr<Module> CurrentProgram = CloneModule(*Test.getProgram());
+ // Generate Module with only Targets inside Current Chunks
+ ExtractChunksFromModule(CurrentChunks, CurrentProgram.get());
+ // Write Module to tmp file
+ SmallString<128> CurrentFilepath =
+ createTmpFile(CurrentProgram.get(), Test.getTmpDir());
+
+ outs() << "Testing with: ";
+ printChunks(CurrentChunks, /*Oneline=*/true);
+ outs() << " | " << sys::path::filename(CurrentFilepath);
+
+ // Current Chunks aren't interesting
+ if (!Test.run(CurrentFilepath)) {
+ outs() << "\n";
+ continue;
+ }
+
+ UninterestingChunks.insert(Chunks[I]);
+ Test.setReducedFilepath(CurrentFilepath);
+ ReducedProgram = std::move(CurrentProgram);
+ outs() << " **** SUCCESS | lines: " << getLines(CurrentFilepath) << "\n";
+ }
+ // Delete uninteresting chunks
+ auto UnwantedChunks = Chunks.end();
+ UnwantedChunks = std::remove_if(Chunks.begin(), Chunks.end(),
+ [UninterestingChunks](const Chunk &C) {
+ return UninterestingChunks.count(C);
+ });
+ Chunks.erase(UnwantedChunks, Chunks.end());
+
+ } while (!UninterestingChunks.empty() || increaseGranularity(Chunks));
+
+ // If we reduced the testcase replace it
+ if (ReducedProgram)
+ Test.setProgram(std::move(ReducedProgram));
+ outs() << "Couldn't increase anymore.\n";
+ outs() << "----------------------------\n";
+}
\ No newline at end of file
diff --git a/llvm/tools/llvm-reduce/deltas/ReduceFunctions.h b/llvm/tools/llvm-reduce/deltas/ReduceFunctions.h
new file mode 100644
--- /dev/null
+++ b/llvm/tools/llvm-reduce/deltas/ReduceFunctions.h
@@ -0,0 +1,20 @@
+//===- ReduceFunctions.h - Specialized Delta Pass -------------------------===//
+//
+// 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
+//
+//===----------------------------------------------------------------------===//
+//
+// This file implements a function which calls the Generic Delta pass in order
+// to reduce functions (and any instruction that calls it) in the provided
+// Module.
+//
+//===----------------------------------------------------------------------===//
+
+#include "Delta.h"
+#include "llvm/Transforms/Utils/Cloning.h"
+
+namespace llvm {
+void reduceFunctionsDeltaPass(TestRunner &Test);
+} // namespace llvm
diff --git a/llvm/tools/llvm-reduce/deltas/ReduceFunctions.cpp b/llvm/tools/llvm-reduce/deltas/ReduceFunctions.cpp
new file mode 100644
--- /dev/null
+++ b/llvm/tools/llvm-reduce/deltas/ReduceFunctions.cpp
@@ -0,0 +1,80 @@
+//===- ReduceFunctions.cpp - Specialized Delta Pass -----------------------===//
+//
+// 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
+//
+//===----------------------------------------------------------------------===//
+//
+// This file implements a function which calls the Generic Delta pass in order
+// to reduce functions (and any instruction that calls it) in the provided
+// Module.
+//
+//===----------------------------------------------------------------------===//
+
+#include "ReduceFunctions.h"
+
+/// Removes all the Defined Functions (as well as their calls)
+/// that aren't inside any of the desired Chunks.
+/// @returns the Module stripped of out-of-chunk functions
+static void extractFunctionsFromModule(const std::vector<Chunk> &ChunksToKeep,
+ Module *Program) {
+ // Get functions inside desired chunks
+ std::set<Function *> FuncsToKeep;
+ unsigned I = 0, FunctionCount = 0;
+ for (auto &F : *Program) {
+ if (!F.isDeclaration() && I < ChunksToKeep.size()) {
+ if (ChunksToKeep[I].contains(++FunctionCount))
+ FuncsToKeep.insert(&F);
+ if (FunctionCount == ChunksToKeep[I].end)
+ ++I;
+ }
+ }
+
+ // Delete out-of-chunk functions, and replace their calls with undef
+ std::vector<Function *> FuncsToRemove;
+ for (auto &F : *Program) {
+ if (!F.isDeclaration() && !FuncsToKeep.count(&F)) {
+ F.replaceAllUsesWith(UndefValue::get(F.getType()));
+ FuncsToRemove.push_back(&F);
+ }
+ }
+ for (auto *F : FuncsToRemove)
+ F->eraseFromParent();
+
+ // Delete instructions with undef calls
+ std::vector<Instruction *> InstToRemove;
+ for (auto &F : *Program)
+ for (auto &BB : F)
+ for (auto &I : BB)
+ if (auto *Call = dyn_cast<CallInst>(&I))
+ if (!Call->getCalledFunction()) {
+ // Instruction might be stored / used somewhere else
+ I.replaceAllUsesWith(UndefValue::get(I.getType()));
+ InstToRemove.push_back(&I);
+ }
+
+ for (auto *I : InstToRemove)
+ I->eraseFromParent();
+}
+
+/// Counts the amount of non-declaration functions and prints their
+/// respective name & index
+static unsigned countDefinedFunctions(Module *Program) {
+ // TODO: Silence index with --quiet flag
+ outs() << "----------------------------\n";
+ outs() << "Function Index Reference:\n";
+ unsigned FunctionCount = 0;
+ for (auto &F : *Program)
+ if (!F.isDeclaration())
+ outs() << "\t" << ++FunctionCount << ": " << F.getName() << "\n";
+
+ outs() << "----------------------------\n";
+ return FunctionCount;
+}
+
+void llvm::reduceFunctionsDeltaPass(TestRunner &Test) {
+ outs() << "*** Reducing Functions...\n";
+ unsigned Functions = countDefinedFunctions(Test.getProgram());
+ runDeltaPass(Test, Functions, extractFunctionsFromModule);
+}
\ No newline at end of file
diff --git a/llvm/tools/llvm-reduce/llvm-reduce.cpp b/llvm/tools/llvm-reduce/llvm-reduce.cpp
new file mode 100644
--- /dev/null
+++ b/llvm/tools/llvm-reduce/llvm-reduce.cpp
@@ -0,0 +1,105 @@
+//===- llvm-reduce.cpp - The LLVM Delta Reduction utility -----------------===//
+//
+// 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
+//
+//===----------------------------------------------------------------------===//
+//
+// This program tries to reduce an IR test case for a given interesting-ness
+// test. It runs multiple delta debugging passes in order to minimize the input
+// file. It's worth noting that this is a *temporary* tool that will eventually
+// be integrated into the bugpoint tool itself.
+//
+//===----------------------------------------------------------------------===//
+
+#include "DeltaManager.h"
+#include "llvm/ADT/SmallString.h"
+#include "llvm/IR/LLVMContext.h"
+#include "llvm/IR/Verifier.h"
+#include "llvm/IRReader/IRReader.h"
+#include "llvm/Support/CommandLine.h"
+#include "llvm/Support/InitLLVM.h"
+#include "llvm/Support/SourceMgr.h"
+#include "llvm/Support/raw_ostream.h"
+#include <system_error>
+#include <vector>
+
+using namespace llvm;
+
+static cl::opt<bool> Help("h", cl::desc("Alias for -help"), cl::Hidden);
+static cl::opt<bool> Version("v", cl::desc("Alias for -version"), cl::Hidden);
+
+static cl::opt<std::string> InputFilename(cl::Positional, cl::Required,
+ cl::desc("<input llvm ll/bc file>"));
+
+static cl::opt<std::string>
+ TestFilename("test", cl::Required,
+ cl::desc("Name of the interesting-ness test to be run"));
+
+static cl::list<std::string>
+ TestArguments("test-arg", cl::ZeroOrMore,
+ cl::desc("Arguments passed onto the interesting-ness test"));
+
+static cl::opt<std::string>
+ OutputFilename("output",
+ cl::desc("Specify the output file. default: reduced.ll"));
+static cl::alias OutputFileAlias("o", cl::desc("Alias for -output"),
+ cl::aliasopt(OutputFilename));
+
+static cl::opt<bool>
+ ReplaceInput("in-place",
+ cl::desc("WARNING: This option will replace your input file"
+ "with the reduced version!"));
+
+// Parses IR into a Module and verifies it
+static std::unique_ptr<Module> parseInputFile(StringRef Filename,
+ LLVMContext &Ctxt) {
+ SMDiagnostic Err;
+ std::unique_ptr<Module> Result = parseIRFile(Filename, Err, Ctxt);
+ if (!Result) {
+ Err.print("llvm-reduce", errs());
+ return Result;
+ }
+
+ if (verifyModule(*Result, &errs())) {
+ errs() << "Error: " << Filename << " - input module is broken!\n";
+ return std::unique_ptr<Module>();
+ }
+
+ return Result;
+}
+
+int main(int argc, char **argv) {
+ InitLLVM X(argc, argv);
+
+ cl::ParseCommandLineOptions(argc, argv, "LLVM automatic testcase reducer.\n");
+
+ LLVMContext Context;
+ std::unique_ptr<Module> OriginalProgram =
+ parseInputFile(InputFilename, Context);
+
+ // Initialize test environment
+ TestRunner Tester(TestFilename, TestArguments, InputFilename);
+ Tester.setProgram(std::move(OriginalProgram));
+
+ // Try to reduce code
+ runDeltaPasses(Tester);
+ StringRef ReducedFilename = sys::path::filename(Tester.getReducedFilepath());
+
+ if (ReducedFilename == InputFilename) {
+ outs() << "\nCouldnt reduce input :/\n";
+ } else {
+ if (ReplaceInput) // In-place
+ OutputFilename = InputFilename.c_str();
+ else if (OutputFilename.empty())
+ OutputFilename = "reduced.ll";
+ else
+ OutputFilename += ".ll";
+
+ sys::fs::copy_file(Tester.getReducedFilepath(), OutputFilename);
+ outs() << "\nDone reducing! Reduced IR to file: " << OutputFilename << "\n";
+ }
+
+ return 0;
+}