[llvm] r179140 - Generalize the PassConfig API and remove addFinalizeRegAlloc().
Andrew Trick
atrick at apple.com
Tue Apr 9 18:06:56 PDT 2013
Author: atrick
Date: Tue Apr 9 20:06:56 2013
New Revision: 179140
URL: http://llvm.org/viewvc/llvm-project?rev=179140&view=rev
Log:
Generalize the PassConfig API and remove addFinalizeRegAlloc().
The target hooks are getting out of hand. What does it mean to run
before or after regalloc anyway? Allowing either Pass* or AnalysisID
pass identification should make it much easier for targets to use the
substitutePass and insertPass APIs, and create less need for badly
named target hooks.
Modified:
llvm/trunk/include/llvm/CodeGen/Passes.h
llvm/trunk/lib/CodeGen/Passes.cpp
Modified: llvm/trunk/include/llvm/CodeGen/Passes.h
URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/include/llvm/CodeGen/Passes.h?rev=179140&r1=179139&r2=179140&view=diff
==============================================================================
--- llvm/trunk/include/llvm/CodeGen/Passes.h (original)
+++ llvm/trunk/include/llvm/CodeGen/Passes.h Tue Apr 9 20:06:56 2013
@@ -35,6 +35,46 @@ namespace llvm {
class PassConfigImpl;
+/// Discriminated union of Pass ID types.
+///
+/// The PassConfig API prefers dealing with IDs because they are safer and more
+/// efficient. IDs decouple configuration from instantiation. This way, when a
+/// pass is overriden, it isn't unnecessarily instantiated. It is also unsafe to
+/// refer to a Pass pointer after adding it to a pass manager, which deletes
+/// redundant pass instances.
+///
+/// However, it is convient to directly instantiate target passes with
+/// non-default ctors. These often don't have a registered PassInfo. Rather than
+/// force all target passes to implement the pass registry boilerplate, allow
+/// the PassConfig API to handle either type.
+///
+/// AnalysisID is sadly char*, so PointerIntPair won't work.
+class IdentifyingPassPtr {
+ void *P;
+ bool IsInstance;
+public:
+ IdentifyingPassPtr(): P(0), IsInstance(false) {}
+ IdentifyingPassPtr(AnalysisID IDPtr): P((void*)IDPtr), IsInstance(false) {}
+ IdentifyingPassPtr(Pass *InstancePtr)
+ : P((void*)InstancePtr), IsInstance(true) {}
+
+ bool isValid() const { return P; }
+ bool isInstance() const { return IsInstance; }
+
+ AnalysisID getID() const {
+ assert(!IsInstance && "Not a Pass ID");
+ return (AnalysisID)P;
+ }
+ Pass *getInstance() const {
+ assert(IsInstance && "Not a Pass Instance");
+ return (Pass *)P;
+ }
+};
+
+template <> struct isPodLike<IdentifyingPassPtr> {
+ static const bool value = true;
+};
+
/// Target-Independent Code Generator Pass Configuration Options.
///
/// This is an ImmutablePass solely for the purpose of exposing CodeGen options
@@ -117,20 +157,22 @@ public:
/// Allow the target to override a specific pass without overriding the pass
/// pipeline. When passes are added to the standard pipeline at the
/// point where StandardID is expected, add TargetID in its place.
- void substitutePass(AnalysisID StandardID, AnalysisID TargetID);
+ void substitutePass(AnalysisID StandardID, IdentifyingPassPtr TargetID);
/// Insert InsertedPassID pass after TargetPassID pass.
- void insertPass(AnalysisID TargetPassID, AnalysisID InsertedPassID);
+ void insertPass(AnalysisID TargetPassID, IdentifyingPassPtr InsertedPassID);
/// Allow the target to enable a specific standard pass by default.
void enablePass(AnalysisID PassID) { substitutePass(PassID, PassID); }
/// Allow the target to disable a specific standard pass by default.
- void disablePass(AnalysisID PassID) { substitutePass(PassID, 0); }
+ void disablePass(AnalysisID PassID) {
+ substitutePass(PassID, IdentifyingPassPtr());
+ }
/// Return the pass substituted for StandardID by the target.
/// If no substitution exists, return StandardID.
- AnalysisID getPassSubstitution(AnalysisID StandardID) const;
+ IdentifyingPassPtr getPassSubstitution(AnalysisID StandardID) const;
/// Return true if the optimized regalloc pipeline is enabled.
bool getOptimizeRegAlloc() const;
@@ -222,17 +264,6 @@ protected:
return false;
}
- /// addFinalizeRegAlloc - This method may be implemented by targets that want
- /// to run passes within the regalloc pipeline, immediately after the register
- /// allocation pass itself. These passes run as soon as virtual regisiters
- /// have been rewritten to physical registers but before and other postRA
- /// optimization happens. Targets that have marked instructions for bundling
- /// must have finalized those bundles by the time these passes have run,
- /// because subsequent passes are not guaranteed to be bundle-aware.
- virtual bool addFinalizeRegAlloc() {
- return false;
- }
-
/// addPostRegAlloc - This method may be implemented by targets that want to
/// run passes after register allocation pass pipeline but before
/// prolog-epilog insertion. This should return true if -print-machineinstrs
Modified: llvm/trunk/lib/CodeGen/Passes.cpp
URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/lib/CodeGen/Passes.cpp?rev=179140&r1=179139&r2=179140&view=diff
==============================================================================
--- llvm/trunk/lib/CodeGen/Passes.cpp (original)
+++ llvm/trunk/lib/CodeGen/Passes.cpp Tue Apr 9 20:06:56 2013
@@ -93,9 +93,10 @@ static cl::opt<bool> EarlyLiveIntervals(
/// simple binary flags that either suppress the pass or do nothing.
/// i.e. -disable-mypass=false has no effect.
/// These should be converted to boolOrDefault in order to use applyOverride.
-static AnalysisID applyDisable(AnalysisID PassID, bool Override) {
+static IdentifyingPassPtr applyDisable(IdentifyingPassPtr PassID,
+ bool Override) {
if (Override)
- return 0;
+ return IdentifyingPassPtr();
return PassID;
}
@@ -103,19 +104,20 @@ static AnalysisID applyDisable(AnalysisI
/// flags with ternary conditions. TargetID is passed through by default. The
/// pass is suppressed when the option is false. When the option is true, the
/// StandardID is selected if the target provides no default.
-static AnalysisID applyOverride(AnalysisID TargetID, cl::boolOrDefault Override,
- AnalysisID StandardID) {
+static IdentifyingPassPtr applyOverride(IdentifyingPassPtr TargetID,
+ cl::boolOrDefault Override,
+ AnalysisID StandardID) {
switch (Override) {
case cl::BOU_UNSET:
return TargetID;
case cl::BOU_TRUE:
- if (TargetID)
+ if (TargetID.isValid())
return TargetID;
if (StandardID == 0)
report_fatal_error("Target cannot enable pass");
return StandardID;
case cl::BOU_FALSE:
- return 0;
+ return IdentifyingPassPtr();
}
llvm_unreachable("Invalid command line option state");
}
@@ -132,7 +134,8 @@ static AnalysisID applyOverride(Analysis
/// StandardID may be a pseudo ID. In that case TargetID is the name of the real
/// pass to run. This allows multiple options to control a single pass depending
/// on where in the pipeline that pass is added.
-static AnalysisID overridePass(AnalysisID StandardID, AnalysisID TargetID) {
+static IdentifyingPassPtr overridePass(AnalysisID StandardID,
+ IdentifyingPassPtr TargetID) {
if (StandardID == &PostRASchedulerID)
return applyDisable(TargetID, DisablePostRA);
@@ -200,11 +203,11 @@ public:
// user interface. For example, a target may disable a standard pass by
// default by substituting a pass ID of zero, and the user may still enable
// that standard pass with an explicit command line option.
- DenseMap<AnalysisID,AnalysisID> TargetPasses;
+ DenseMap<AnalysisID,IdentifyingPassPtr> TargetPasses;
/// Store the pairs of <AnalysisID, AnalysisID> of which the second pass
/// is inserted after each instance of the first one.
- SmallVector<std::pair<AnalysisID, AnalysisID>, 4> InsertedPasses;
+ SmallVector<std::pair<AnalysisID, IdentifyingPassPtr>, 4> InsertedPasses;
};
} // namespace llvm
@@ -239,9 +242,13 @@ TargetPassConfig::TargetPassConfig(Targe
/// Insert InsertedPassID pass after TargetPassID.
void TargetPassConfig::insertPass(AnalysisID TargetPassID,
- AnalysisID InsertedPassID) {
- assert(TargetPassID != InsertedPassID && "Insert a pass after itself!");
- std::pair<AnalysisID, AnalysisID> P(TargetPassID, InsertedPassID);
+ IdentifyingPassPtr InsertedPassID) {
+ assert((!InsertedPassID.isInstance() &&
+ TargetPassID != InsertedPassID.getID()) ||
+ (InsertedPassID.isInstance() &&
+ TargetPassID != InsertedPassID.getInstance()->getPassID()) &&
+ "Insert a pass after itself!");
+ std::pair<AnalysisID, IdentifyingPassPtr> P(TargetPassID, InsertedPassID);
Impl->InsertedPasses.push_back(P);
}
@@ -265,12 +272,12 @@ void TargetPassConfig::setOpt(bool &Opt,
}
void TargetPassConfig::substitutePass(AnalysisID StandardID,
- AnalysisID TargetID) {
+ IdentifyingPassPtr TargetID) {
Impl->TargetPasses[StandardID] = TargetID;
}
-AnalysisID TargetPassConfig::getPassSubstitution(AnalysisID ID) const {
- DenseMap<AnalysisID, AnalysisID>::const_iterator
+IdentifyingPassPtr TargetPassConfig::getPassSubstitution(AnalysisID ID) const {
+ DenseMap<AnalysisID, IdentifyingPassPtr>::const_iterator
I = Impl->TargetPasses.find(ID);
if (I == Impl->TargetPasses.end())
return ID;
@@ -303,24 +310,39 @@ void TargetPassConfig::addPass(Pass *P)
/// Add a CodeGen pass at this point in the pipeline after checking for target
/// and command line overrides.
+///
+/// addPass cannot return a pointer to the pass instance because is internal the
+/// PassManager and the instance we create here may already be freed.
AnalysisID TargetPassConfig::addPass(AnalysisID PassID) {
- AnalysisID TargetID = getPassSubstitution(PassID);
- AnalysisID FinalID = overridePass(PassID, TargetID);
- if (FinalID == 0)
- return FinalID;
-
- Pass *P = Pass::createPass(FinalID);
- if (!P)
- llvm_unreachable("Pass ID not registered");
- addPass(P);
+ IdentifyingPassPtr TargetID = getPassSubstitution(PassID);
+ IdentifyingPassPtr FinalPtr = overridePass(PassID, TargetID);
+ if (!FinalPtr.isValid())
+ return 0;
+
+ Pass *P;
+ if (FinalPtr.isInstance())
+ P = FinalPtr.getInstance();
+ else {
+ P = Pass::createPass(FinalPtr.getID());
+ if (!P)
+ llvm_unreachable("Pass ID not registered");
+ }
+ AnalysisID FinalID = P->getPassID();
+ addPass(P); // Ends the lifetime of P.
+
// Add the passes after the pass P if there is any.
- for (SmallVector<std::pair<AnalysisID, AnalysisID>, 4>::iterator
+ for (SmallVector<std::pair<AnalysisID, IdentifyingPassPtr>, 4>::iterator
I = Impl->InsertedPasses.begin(), E = Impl->InsertedPasses.end();
I != E; ++I) {
if ((*I).first == PassID) {
- assert((*I).second && "Illegal Pass ID!");
- Pass *NP = Pass::createPass((*I).second);
- assert(NP && "Pass ID not registered");
+ assert((*I).second.isValid() && "Illegal Pass ID!");
+ Pass *NP;
+ if ((*I).second.isInstance())
+ NP = (*I).second.getInstance();
+ else {
+ NP = Pass::createPass((*I).second.getID());
+ assert(NP && "Pass ID not registered");
+ }
addPass(NP);
}
}
@@ -687,14 +709,6 @@ void TargetPassConfig::addOptimizedRegAl
addPass(&VirtRegRewriterID);
printAndVerify("After Virtual Register Rewriter");
- // FinalizeRegAlloc is convenient until MachineInstrBundles is more mature,
- // but eventually, all users of it should probably be moved to addPostRA and
- // it can go away. Currently, it's the intended place for targets to run
- // FinalizeMachineBundles, because passes other than MachineScheduling an
- // RegAlloc itself may not be aware of bundles.
- if (addFinalizeRegAlloc())
- printAndVerify("After RegAlloc finalization");
-
// Perform stack slot coloring and post-ra machine LICM.
//
// FIXME: Re-enable coloring with register when it's capable of adding
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