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/ADT/STLExtras.h"
#include "llvm/IR/LLVMContext.h"
#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
using namespace llvm;
[PM] Switch analysis managers to be threaded through the run methods rather than the constructors of passes. This simplifies the APIs of passes significantly and removes an error prone pattern where the *same* manager had to be given to every different layer. With the new API the analysis managers themselves will have to be cross connected with proxy analyses that allow a pass at one layer to query for the analysis manager of another layer. The proxy will both expose a handle to the other layer's manager and it will provide the invalidation hooks to ensure things remain consistent across layers. Finally, the outer-most analysis manager has to be passed to the run method of the outer-most pass manager. The rest of the propagation is automatic. I've used SFINAE again to allow passes to completely disregard the analysis manager if they don't need or want to care. This helps keep simple things simple for users of the new pass manager. Also, the system specifically supports passing a null pointer into the outer-most run method if your pass pipeline neither needs nor wants to deal with analyses. I find this of dubious utility as while some *passes* don't care about analysis, I'm not sure there are any real-world users of the pass manager itself that need to avoid even creating an analysis manager. But it is easy to support, so there we go. Finally I renamed the module proxy for the function analysis manager to the more verbose but less confusing name of FunctionAnalysisManagerModuleProxy. I hate this name, but I have no idea what else to name these things. I'm expecting in the fullness of time to potentially have the complete cross product of types at the proxy layer: {Module,SCC,Function,Loop,Region}AnalysisManager{Module,SCC,Function,Loop,Region}Proxy (except for XAnalysisManagerXProxy which doesn't make any sense) This should make it somewhat easier to do the next phases which is to build the upward proxy and get its invalidation correct, as well as to make the invalidation within the Module -> Function mapping pass be more fine grained so as to invalidate fewer fuction analyses. After all of the proxy analyses are done and the invalidation working, I'll finally be able to start working on the next two fun fronts: how to adapt an existing pass to work in both the legacy pass world and the new one, and building the SCC, Loop, and Region counterparts. Fun times! llvm-svn: 195400
2013-11-22 08:43:29 +08:00
char FunctionAnalysisManagerModuleProxy::PassID;
[PM] Switch analysis managers to be threaded through the run methods rather than the constructors of passes. This simplifies the APIs of passes significantly and removes an error prone pattern where the *same* manager had to be given to every different layer. With the new API the analysis managers themselves will have to be cross connected with proxy analyses that allow a pass at one layer to query for the analysis manager of another layer. The proxy will both expose a handle to the other layer's manager and it will provide the invalidation hooks to ensure things remain consistent across layers. Finally, the outer-most analysis manager has to be passed to the run method of the outer-most pass manager. The rest of the propagation is automatic. I've used SFINAE again to allow passes to completely disregard the analysis manager if they don't need or want to care. This helps keep simple things simple for users of the new pass manager. Also, the system specifically supports passing a null pointer into the outer-most run method if your pass pipeline neither needs nor wants to deal with analyses. I find this of dubious utility as while some *passes* don't care about analysis, I'm not sure there are any real-world users of the pass manager itself that need to avoid even creating an analysis manager. But it is easy to support, so there we go. Finally I renamed the module proxy for the function analysis manager to the more verbose but less confusing name of FunctionAnalysisManagerModuleProxy. I hate this name, but I have no idea what else to name these things. I'm expecting in the fullness of time to potentially have the complete cross product of types at the proxy layer: {Module,SCC,Function,Loop,Region}AnalysisManager{Module,SCC,Function,Loop,Region}Proxy (except for XAnalysisManagerXProxy which doesn't make any sense) This should make it somewhat easier to do the next phases which is to build the upward proxy and get its invalidation correct, as well as to make the invalidation within the Module -> Function mapping pass be more fine grained so as to invalidate fewer fuction analyses. After all of the proxy analyses are done and the invalidation working, I'll finally be able to start working on the next two fun fronts: how to adapt an existing pass to work in both the legacy pass world and the new one, and building the SCC, Loop, and Region counterparts. Fun times! llvm-svn: 195400
2013-11-22 08:43:29 +08:00
FunctionAnalysisManagerModuleProxy::Result
FunctionAnalysisManagerModuleProxy::run(Module &M) {
assert(FAM->empty() && "Function analyses ran prior to the module proxy!");
return Result(*FAM);
}
[PM] Switch analysis managers to be threaded through the run methods rather than the constructors of passes. This simplifies the APIs of passes significantly and removes an error prone pattern where the *same* manager had to be given to every different layer. With the new API the analysis managers themselves will have to be cross connected with proxy analyses that allow a pass at one layer to query for the analysis manager of another layer. The proxy will both expose a handle to the other layer's manager and it will provide the invalidation hooks to ensure things remain consistent across layers. Finally, the outer-most analysis manager has to be passed to the run method of the outer-most pass manager. The rest of the propagation is automatic. I've used SFINAE again to allow passes to completely disregard the analysis manager if they don't need or want to care. This helps keep simple things simple for users of the new pass manager. Also, the system specifically supports passing a null pointer into the outer-most run method if your pass pipeline neither needs nor wants to deal with analyses. I find this of dubious utility as while some *passes* don't care about analysis, I'm not sure there are any real-world users of the pass manager itself that need to avoid even creating an analysis manager. But it is easy to support, so there we go. Finally I renamed the module proxy for the function analysis manager to the more verbose but less confusing name of FunctionAnalysisManagerModuleProxy. I hate this name, but I have no idea what else to name these things. I'm expecting in the fullness of time to potentially have the complete cross product of types at the proxy layer: {Module,SCC,Function,Loop,Region}AnalysisManager{Module,SCC,Function,Loop,Region}Proxy (except for XAnalysisManagerXProxy which doesn't make any sense) This should make it somewhat easier to do the next phases which is to build the upward proxy and get its invalidation correct, as well as to make the invalidation within the Module -> Function mapping pass be more fine grained so as to invalidate fewer fuction analyses. After all of the proxy analyses are done and the invalidation working, I'll finally be able to start working on the next two fun fronts: how to adapt an existing pass to work in both the legacy pass world and the new one, and building the SCC, Loop, and Region counterparts. Fun times! llvm-svn: 195400
2013-11-22 08:43:29 +08:00
FunctionAnalysisManagerModuleProxy::Result::~Result() {
// FAM is cleared in a moved from state where there is nothing to do.
if (!FAM)
return;
// Clear out the analysis manager if we're being destroyed -- it means we
// didn't even see an invalidate call when we got invalidated.
FAM->clear();
}
[PM] Switch analysis managers to be threaded through the run methods rather than the constructors of passes. This simplifies the APIs of passes significantly and removes an error prone pattern where the *same* manager had to be given to every different layer. With the new API the analysis managers themselves will have to be cross connected with proxy analyses that allow a pass at one layer to query for the analysis manager of another layer. The proxy will both expose a handle to the other layer's manager and it will provide the invalidation hooks to ensure things remain consistent across layers. Finally, the outer-most analysis manager has to be passed to the run method of the outer-most pass manager. The rest of the propagation is automatic. I've used SFINAE again to allow passes to completely disregard the analysis manager if they don't need or want to care. This helps keep simple things simple for users of the new pass manager. Also, the system specifically supports passing a null pointer into the outer-most run method if your pass pipeline neither needs nor wants to deal with analyses. I find this of dubious utility as while some *passes* don't care about analysis, I'm not sure there are any real-world users of the pass manager itself that need to avoid even creating an analysis manager. But it is easy to support, so there we go. Finally I renamed the module proxy for the function analysis manager to the more verbose but less confusing name of FunctionAnalysisManagerModuleProxy. I hate this name, but I have no idea what else to name these things. I'm expecting in the fullness of time to potentially have the complete cross product of types at the proxy layer: {Module,SCC,Function,Loop,Region}AnalysisManager{Module,SCC,Function,Loop,Region}Proxy (except for XAnalysisManagerXProxy which doesn't make any sense) This should make it somewhat easier to do the next phases which is to build the upward proxy and get its invalidation correct, as well as to make the invalidation within the Module -> Function mapping pass be more fine grained so as to invalidate fewer fuction analyses. After all of the proxy analyses are done and the invalidation working, I'll finally be able to start working on the next two fun fronts: how to adapt an existing pass to work in both the legacy pass world and the new one, and building the SCC, Loop, and Region counterparts. Fun times! llvm-svn: 195400
2013-11-22 08:43:29 +08:00
bool FunctionAnalysisManagerModuleProxy::Result::invalidate(
Module &M, const PreservedAnalyses &PA) {
// If this proxy isn't marked as preserved, then we can't even invalidate
// individual function analyses, there may be an invalid set of Function
// objects in the cache making it impossible to incrementally preserve them.
// Just clear the entire manager.
if (!PA.preserved(ID()))
FAM->clear();
// Return false to indicate that this result is still a valid proxy.
return false;
}
char ModuleAnalysisManagerFunctionProxy::PassID;