diff --git a/llvm/test/Reduce/Inputs/remove-global-vars.py b/llvm/test/Reduce/Inputs/remove-global-vars.py new file mode 100755 --- /dev/null +++ b/llvm/test/Reduce/Inputs/remove-global-vars.py @@ -0,0 +1,10 @@ +#!/usr/bin/env python + +import sys + +input = open(sys.argv[1], "r") +for line in input: + if "@interesting = global" in line: + sys.exit(0) + +sys.exit(1) # IR isn't interesting diff --git a/llvm/test/Reduce/remove-funcs.ll b/llvm/test/Reduce/remove-funcs.ll --- a/llvm/test/Reduce/remove-funcs.ll +++ b/llvm/test/Reduce/remove-funcs.ll @@ -3,7 +3,7 @@ ; ; RUN: llvm-reduce --test %p/Inputs/remove-funcs.py %s ; RUN: cat reduced.ll | FileCheck %s -; REQUIRES: plugins, shell +; REQUIRES: plugins ; CHECK-NOT: uninteresting1() define i32 @uninteresting1() { diff --git a/llvm/test/Reduce/remove-global-vars.ll b/llvm/test/Reduce/remove-global-vars.ll new file mode 100644 --- /dev/null +++ b/llvm/test/Reduce/remove-global-vars.ll @@ -0,0 +1,38 @@ +; Test that llvm-reduce can remove uninteresting Global Variables as well as +; their direct uses. +; +; RUN: llvm-reduce --test %p/Inputs/remove-global-vars.py %s +; RUN: cat reduced.ll | FileCheck %s +; REQUIRES: plugins + +@uninteresting1 = global i32 0, align 4 +; CHECK: @interesting = global +@interesting = global i32 5, align 4 +; CHECK-NOT: global +@uninteresting2 = global i32 25, align 4 +@uninteresting3 = global i32 50, align 4 + +define i32 @main() { +entry: + %retval = alloca i32, align 4 + store i32 0, i32* %retval, align 4 + ; CHECK-NOT: load i32, i32* @uninteresting2, align 4 + %0 = load i32, i32* @uninteresting2, align 4 + store i32 %0, i32* @interesting, align 4 + ; CHECK-NOT: load i32, i32* @uninteresting3, align 4 + %1 = load i32, i32* @uninteresting3, align 4 + %dec = add nsw i32 %1, -1 + ; CHECK-NOT: store i32 %dec, i32* @uninteresting3, align 4 + store i32 %dec, i32* @uninteresting3, align 4 + ; CHECK: load i32, i32* @interesting, align 4 + %2 = load i32, i32* @interesting, align 4 + ; CHECK-NOT: load i32, i32* @uninteresting2, align 4 + %3 = load i32, i32* @uninteresting2, align 4 + %add = add nsw i32 %2, %3 + ; CHECK-NOT: store i32 %add, i32* @uninteresting1, align 4 + store i32 %add, i32* @uninteresting1, align 4 + store i32 10, i32* @interesting, align 4 + ; CHECK: load i32, i32* @interesting, align 4 + %4 = load i32, i32* @interesting, align 4 + ret i32 0 +} diff --git a/llvm/tools/llvm-reduce/CMakeLists.txt b/llvm/tools/llvm-reduce/CMakeLists.txt --- a/llvm/tools/llvm-reduce/CMakeLists.txt +++ b/llvm/tools/llvm-reduce/CMakeLists.txt @@ -17,6 +17,7 @@ TestRunner.cpp deltas/Delta.cpp deltas/ReduceFunctions.cpp + deltas/ReduceGlobalVars.cpp DEPENDS intrinsics_gen diff --git a/llvm/tools/llvm-reduce/DeltaManager.h b/llvm/tools/llvm-reduce/DeltaManager.h --- a/llvm/tools/llvm-reduce/DeltaManager.h +++ b/llvm/tools/llvm-reduce/DeltaManager.h @@ -14,11 +14,16 @@ #include "TestRunner.h" #include "deltas/Delta.h" #include "deltas/ReduceFunctions.h" +#include "deltas/ReduceGlobalVars.h" namespace llvm { +// TODO: Add function which can call specified delta passes (for unit tests) inline void runDeltaPasses(TestRunner &Tester) { + outs() << "Reducing functions...\n"; reduceFunctionsDeltaPass(Tester); + outs() << "Reducing GVs...\n"; + reduceGlobalsDeltaPass(Tester); // TODO: Implement the remaining Delta Passes } diff --git a/llvm/tools/llvm-reduce/deltas/Delta.cpp b/llvm/tools/llvm-reduce/deltas/Delta.cpp --- a/llvm/tools/llvm-reduce/deltas/Delta.cpp +++ b/llvm/tools/llvm-reduce/deltas/Delta.cpp @@ -114,16 +114,15 @@ outs() << "\nNothing to reduce\n"; return; } - - std::vector Chunks = {{1, Targets}}; - std::set UninterestingChunks; - std::unique_ptr ReducedProgram; - if (!Test.run(Test.getReducedFilepath())) { outs() << "\nInput isn't interesting! Verify interesting-ness test\n"; return; } + std::vector Chunks = {{1, Targets}}; + std::set UninterestingChunks; + std::unique_ptr ReducedProgram; + if (!increaseGranularity(Chunks)) { outs() << "\nAlready at minimum size. Cannot reduce anymore.\n"; return; diff --git a/llvm/tools/llvm-reduce/DeltaManager.h b/llvm/tools/llvm-reduce/deltas/ReduceGlobalVars.h copy from llvm/tools/llvm-reduce/DeltaManager.h copy to llvm/tools/llvm-reduce/deltas/ReduceGlobalVars.h --- a/llvm/tools/llvm-reduce/DeltaManager.h +++ b/llvm/tools/llvm-reduce/deltas/ReduceGlobalVars.h @@ -1,4 +1,4 @@ -//===- DeltaManager.h - Runs Delta Passes to reduce Input -----------------===// +//===- RemoveGlobalVars.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. @@ -6,20 +6,15 @@ // //===----------------------------------------------------------------------===// // -// This file calls each specialized Delta pass in order to reduce the input IR -// file. +// This file implements a function which calls the Generic Delta pass in order +// to reduce initialized Global Variables in the provided Module. // //===----------------------------------------------------------------------===// -#include "TestRunner.h" -#include "deltas/Delta.h" -#include "deltas/ReduceFunctions.h" +#include "Delta.h" +#include "llvm/IR/Value.h" +#include "llvm/Transforms/Utils/Cloning.h" namespace llvm { - -inline void runDeltaPasses(TestRunner &Tester) { - reduceFunctionsDeltaPass(Tester); - // TODO: Implement the remaining Delta Passes -} - +void reduceGlobalsDeltaPass(TestRunner &Test); } // namespace llvm diff --git a/llvm/tools/llvm-reduce/deltas/ReduceGlobalVars.cpp b/llvm/tools/llvm-reduce/deltas/ReduceGlobalVars.cpp new file mode 100644 --- /dev/null +++ b/llvm/tools/llvm-reduce/deltas/ReduceGlobalVars.cpp @@ -0,0 +1,72 @@ +//===- RemoveGlobalVars.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 initialized Global Variables in the provided Module. +// +//===----------------------------------------------------------------------===// + +#include "ReduceGlobalVars.h" + +/// Removes all the Initialized GVs that aren't inside the desired Chunks. +/// @returns the Module stripped of out-of-chunk GVs +static void extractGVsFromModule(std::vector ChunksToKeep, + Module *Program) { + // Get GVs inside desired chunks + std::set GVsToKeep; + unsigned I = 0, GVCount = 0; + for (auto &GV : Program->globals()) + if (GV.hasInitializer() && I < ChunksToKeep.size()) { + if (ChunksToKeep[I].contains(++GVCount)) + GVsToKeep.insert(&GV); + if (GVCount == ChunksToKeep[I].end) + ++I; + } + + // Delete out-of-chunk GVs and their uses + std::vector ToRemove; + std::vector InstToRemove; + for (auto &GV : Program->globals()) + if (GV.hasInitializer() && !GVsToKeep.count(&GV)) { + for (auto U : GV.users()) + if (auto *Inst = dyn_cast(U)) + InstToRemove.push_back(Inst); + + GV.replaceAllUsesWith(UndefValue::get(GV.getType())); + ToRemove.push_back(&GV); + } + + // Delete Instruction uses of unwanted GVs + for (auto *Inst : InstToRemove) { + Inst->replaceAllUsesWith(UndefValue::get(Inst->getType())); + Inst->eraseFromParent(); + } + + for (auto *GV : ToRemove) + GV->eraseFromParent(); +} + +/// Counts the amount of initialized GVs and displays their +/// respective name & index +static int countGVs(Module *Program) { + // TODO: Silence index with --quiet flag + outs() << "----------------------------\n"; + outs() << "GlobalVariable Index Reference:\n"; + int GVCount = 0; + for (auto &GV : Program->globals()) + if (GV.hasInitializer()) + outs() << "\t" << ++GVCount << ": " << GV.getName() << "\n"; + outs() << "----------------------------\n"; + return GVCount; +} + +void llvm::reduceGlobalsDeltaPass(TestRunner &Test) { + outs() << "*** Reducing GVs...\n"; + unsigned GVCount = countGVs(Test.getProgram()); + runDeltaPass(Test, GVCount, extractGVsFromModule); +}