llvm/lib/Transforms/IPO/IPO.cpp
Peter Collingbourne 5a81e14385 Introduce bitset metadata format and bitset lowering pass.
This patch introduces a new mechanism that allows IR modules to co-operatively
build pointer sets corresponding to addresses within a given set of
globals. One particular use case for this is to allow a C++ program to
efficiently verify (at each call site) that a vtable pointer is in the set
of valid vtable pointers for the class or its derived classes. One way of
doing this is for a toolchain component to build, for each class, a bit set
that maps to the memory region allocated for the vtables, such that each 1
bit in the bit set maps to a valid vtable for that class, and lay out the
vtables next to each other, to minimize the total size of the bit sets.

The patch introduces a metadata format for representing pointer sets, an
'@llvm.bitset.test' intrinsic and an LTO lowering pass that lays out the globals
and builds the bitsets, and documents the new feature.

Differential Revision: http://reviews.llvm.org/D7288

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@230054 91177308-0d34-0410-b5e6-96231b3b80d8
2015-02-20 20:30:47 +00:00

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3.4 KiB
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//===-- IPO.cpp -----------------------------------------------------------===//
//
// The LLVM Compiler Infrastructure
//
// This file is distributed under the University of Illinois Open Source
// License. See LICENSE.TXT for details.
//
//===----------------------------------------------------------------------===//
//
// This file implements the common infrastructure (including C bindings) for
// libLLVMIPO.a, which implements several transformations over the LLVM
// intermediate representation.
//
//===----------------------------------------------------------------------===//
#include "llvm-c/Initialization.h"
#include "llvm-c/Transforms/IPO.h"
#include "llvm/InitializePasses.h"
#include "llvm/IR/LegacyPassManager.h"
#include "llvm/Transforms/IPO.h"
using namespace llvm;
void llvm::initializeIPO(PassRegistry &Registry) {
initializeArgPromotionPass(Registry);
initializeConstantMergePass(Registry);
initializeDAEPass(Registry);
initializeDAHPass(Registry);
initializeFunctionAttrsPass(Registry);
initializeGlobalDCEPass(Registry);
initializeGlobalOptPass(Registry);
initializeIPCPPass(Registry);
initializeAlwaysInlinerPass(Registry);
initializeSimpleInlinerPass(Registry);
initializeInternalizePassPass(Registry);
initializeLoopExtractorPass(Registry);
initializeBlockExtractorPassPass(Registry);
initializeSingleLoopExtractorPass(Registry);
initializeLowerBitSetsPass(Registry);
initializeMergeFunctionsPass(Registry);
initializePartialInlinerPass(Registry);
initializePruneEHPass(Registry);
initializeStripDeadPrototypesPassPass(Registry);
initializeStripSymbolsPass(Registry);
initializeStripDebugDeclarePass(Registry);
initializeStripDeadDebugInfoPass(Registry);
initializeStripNonDebugSymbolsPass(Registry);
initializeBarrierNoopPass(Registry);
}
void LLVMInitializeIPO(LLVMPassRegistryRef R) {
initializeIPO(*unwrap(R));
}
void LLVMAddArgumentPromotionPass(LLVMPassManagerRef PM) {
unwrap(PM)->add(createArgumentPromotionPass());
}
void LLVMAddConstantMergePass(LLVMPassManagerRef PM) {
unwrap(PM)->add(createConstantMergePass());
}
void LLVMAddDeadArgEliminationPass(LLVMPassManagerRef PM) {
unwrap(PM)->add(createDeadArgEliminationPass());
}
void LLVMAddFunctionAttrsPass(LLVMPassManagerRef PM) {
unwrap(PM)->add(createFunctionAttrsPass());
}
void LLVMAddFunctionInliningPass(LLVMPassManagerRef PM) {
unwrap(PM)->add(createFunctionInliningPass());
}
void LLVMAddAlwaysInlinerPass(LLVMPassManagerRef PM) {
unwrap(PM)->add(llvm::createAlwaysInlinerPass());
}
void LLVMAddGlobalDCEPass(LLVMPassManagerRef PM) {
unwrap(PM)->add(createGlobalDCEPass());
}
void LLVMAddGlobalOptimizerPass(LLVMPassManagerRef PM) {
unwrap(PM)->add(createGlobalOptimizerPass());
}
void LLVMAddIPConstantPropagationPass(LLVMPassManagerRef PM) {
unwrap(PM)->add(createIPConstantPropagationPass());
}
void LLVMAddPruneEHPass(LLVMPassManagerRef PM) {
unwrap(PM)->add(createPruneEHPass());
}
void LLVMAddIPSCCPPass(LLVMPassManagerRef PM) {
unwrap(PM)->add(createIPSCCPPass());
}
void LLVMAddInternalizePass(LLVMPassManagerRef PM, unsigned AllButMain) {
std::vector<const char *> Export;
if (AllButMain)
Export.push_back("main");
unwrap(PM)->add(createInternalizePass(Export));
}
void LLVMAddStripDeadPrototypesPass(LLVMPassManagerRef PM) {
unwrap(PM)->add(createStripDeadPrototypesPass());
}
void LLVMAddStripSymbolsPass(LLVMPassManagerRef PM) {
unwrap(PM)->add(createStripSymbolsPass());
}