llvm-project/llvm/lib/IR/PassManager.cpp

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2014-03-20 02:41:38 +08:00
//===- PassManager.cpp - Infrastructure for managing & running IR passes --===//
Introduce an AnalysisManager which is like a pass manager but with a lot more smarts in it. This is where most of the interesting logic that used to live in the implicit-scheduling-hackery of the old pass manager will live. Like the previous commits, note that this is a very early prototype! I expect substantial changes before this is ready to use. The core of the design is the following: - We have an AnalysisManager which can be used across a series of passes over a module. - The code setting up a pass pipeline registers the analyses available with the manager. - Individual transform passes can check than an analysis manager provides the analyses they require in order to fail-fast. - There is *no* implicit registration or scheduling. - Analysis passes are different from other passes: they produce an analysis result that is cached and made available via the analysis manager. - Cached results are invalidated automatically by the pass managers. - When a transform pass requests an analysis result, either the analysis is run to produce the result or a cached result is provided. There are a few aspects of this design that I *know* will change in subsequent commits: - Currently there is no "preservation" system, that needs to be added. - All of the analysis management should move up to the analysis library. - The analysis management needs to support at least SCC passes. Maybe loop passes. Living in the analysis library will facilitate this. - Need support for analyses which are *both* module and function passes. - Need support for pro-actively running module analyses to have cached results within a function pass manager. - Need a clear design for "immutable" passes. - Need support for requesting cached results when available and not re-running the pass even if that would be necessary. - Need more thorough testing of all of this infrastructure. There are other aspects that I view as open questions I'm hoping to resolve as I iterate a bit on the infrastructure, and especially as I start writing actual passes against this. - Should we have separate management layers for function, module, and SCC analyses? I think "yes", but I'm not yet ready to switch the code. Adding SCC support will likely resolve this definitively. - How should the 'require' functionality work? Should *that* be the only way to request results to ensure that passes always require things? - How should preservation work? - Probably some other things I'm forgetting. =] Look forward to more patches in shorter order now that this is in place. llvm-svn: 194538
2013-11-13 09:12:08 +08:00
//
// The LLVM Compiler Infrastructure
//
// This file is distributed under the University of Illinois Open Source
// License. See LICENSE.TXT for details.
//
//===----------------------------------------------------------------------===//
#include "llvm/IR/PassManager.h"
Introduce an AnalysisManager which is like a pass manager but with a lot more smarts in it. This is where most of the interesting logic that used to live in the implicit-scheduling-hackery of the old pass manager will live. Like the previous commits, note that this is a very early prototype! I expect substantial changes before this is ready to use. The core of the design is the following: - We have an AnalysisManager which can be used across a series of passes over a module. - The code setting up a pass pipeline registers the analyses available with the manager. - Individual transform passes can check than an analysis manager provides the analyses they require in order to fail-fast. - There is *no* implicit registration or scheduling. - Analysis passes are different from other passes: they produce an analysis result that is cached and made available via the analysis manager. - Cached results are invalidated automatically by the pass managers. - When a transform pass requests an analysis result, either the analysis is run to produce the result or a cached result is provided. There are a few aspects of this design that I *know* will change in subsequent commits: - Currently there is no "preservation" system, that needs to be added. - All of the analysis management should move up to the analysis library. - The analysis management needs to support at least SCC passes. Maybe loop passes. Living in the analysis library will facilitate this. - Need support for analyses which are *both* module and function passes. - Need support for pro-actively running module analyses to have cached results within a function pass manager. - Need a clear design for "immutable" passes. - Need support for requesting cached results when available and not re-running the pass even if that would be necessary. - Need more thorough testing of all of this infrastructure. There are other aspects that I view as open questions I'm hoping to resolve as I iterate a bit on the infrastructure, and especially as I start writing actual passes against this. - Should we have separate management layers for function, module, and SCC analyses? I think "yes", but I'm not yet ready to switch the code. Adding SCC support will likely resolve this definitively. - How should the 'require' functionality work? Should *that* be the only way to request results to ensure that passes always require things? - How should preservation work? - Probably some other things I'm forgetting. =] Look forward to more patches in shorter order now that this is in place. llvm-svn: 194538
2013-11-13 09:12:08 +08:00
#include "llvm/ADT/STLExtras.h"
#include "llvm/IR/LLVMContext.h"
Introduce an AnalysisManager which is like a pass manager but with a lot more smarts in it. This is where most of the interesting logic that used to live in the implicit-scheduling-hackery of the old pass manager will live. Like the previous commits, note that this is a very early prototype! I expect substantial changes before this is ready to use. The core of the design is the following: - We have an AnalysisManager which can be used across a series of passes over a module. - The code setting up a pass pipeline registers the analyses available with the manager. - Individual transform passes can check than an analysis manager provides the analyses they require in order to fail-fast. - There is *no* implicit registration or scheduling. - Analysis passes are different from other passes: they produce an analysis result that is cached and made available via the analysis manager. - Cached results are invalidated automatically by the pass managers. - When a transform pass requests an analysis result, either the analysis is run to produce the result or a cached result is provided. There are a few aspects of this design that I *know* will change in subsequent commits: - Currently there is no "preservation" system, that needs to be added. - All of the analysis management should move up to the analysis library. - The analysis management needs to support at least SCC passes. Maybe loop passes. Living in the analysis library will facilitate this. - Need support for analyses which are *both* module and function passes. - Need support for pro-actively running module analyses to have cached results within a function pass manager. - Need a clear design for "immutable" passes. - Need support for requesting cached results when available and not re-running the pass even if that would be necessary. - Need more thorough testing of all of this infrastructure. There are other aspects that I view as open questions I'm hoping to resolve as I iterate a bit on the infrastructure, and especially as I start writing actual passes against this. - Should we have separate management layers for function, module, and SCC analyses? I think "yes", but I'm not yet ready to switch the code. Adding SCC support will likely resolve this definitively. - How should the 'require' functionality work? Should *that* be the only way to request results to ensure that passes always require things? - How should preservation work? - Probably some other things I'm forgetting. =] Look forward to more patches in shorter order now that this is in place. llvm-svn: 194538
2013-11-13 09:12:08 +08:00
using namespace llvm;
// Explicit template instantiations for core template typedefs.
namespace llvm {
template class AllAnalysesOn<Module>;
template class AllAnalysesOn<Function>;
template class PassManager<Module>;
template class PassManager<Function>;
template class AnalysisManager<Module>;
template class AnalysisManager<Function>;
template class InnerAnalysisManagerProxy<FunctionAnalysisManager, Module>;
template class OuterAnalysisManagerProxy<ModuleAnalysisManager, Function>;
}
[PM] Change the static object whose address is used to uniquely identify analyses to have a common type which is enforced rather than using a char object and a `void *` type when used as an identifier. This has a number of advantages. First, it at least helps some of the confusion raised in Justin Lebar's code review of why `void *` was being used everywhere by having a stronger type that connects to documentation about this. However, perhaps more importantly, it addresses a serious issue where the alignment of these pointer-like identifiers was unknown. This made it hard to use them in pointer-like data structures. We were already dodging this in dangerous ways to create the "all analyses" entry. In a subsequent patch I attempted to use these with TinyPtrVector and things fell apart in a very bad way. And it isn't just a compile time or type system issue. Worse than that, the actual alignment of these pointer-like opaque identifiers wasn't guaranteed to be a useful alignment as they were just characters. This change introduces a type to use as the "key" object whose address forms the opaque identifier. This both forces the objects to have proper alignment, and provides type checking that we get it right everywhere. It also makes the types somewhat less mysterious than `void *`. We could go one step further and introduce a truly opaque pointer-like type to return from the `ID()` static function rather than returning `AnalysisKey *`, but that didn't seem to be a clear win so this is just the initial change to get to a reliably typed and aligned object serving is a key for all the analyses. Thanks to Richard Smith and Justin Lebar for helping pick plausible names and avoid making this refactoring many times. =] And thanks to Sean for the super fast review! While here, I've tried to move away from the "PassID" nomenclature entirely as it wasn't really helping and is overloaded with old pass manager constructs. Now we have IDs for analyses, and key objects whose address can be used as IDs. Where possible and clear I've shortened this to just "ID". In a few places I kept "AnalysisID" to make it clear what was being identified. Differential Revision: https://reviews.llvm.org/D27031 llvm-svn: 287783
2016-11-24 01:53:26 +08:00
AnalysisKey PreservedAnalyses::AllAnalysesKey;