[WebAssembly] Add functions for EHScopes
Summary:
There are functions using the term 'funclet' to refer to both
1. an EH scopes, the structure of BBs that starts with
catchpad/cleanuppad and ends with catchret/cleanupret, and
2. a small function that gets outlined in AsmPrinter, which is the
original meaning of 'funclet'.
So far the two have been the same thing; EH scopes are always outlined
in AsmPrinter as funclets at the end of the compilation pipeline. But
now wasm also uses scope-based EH but does not outline those, so we now
need to correctly distinguish those two use cases in functions.
This patch splits `MachineBasicBlock::isFuncletEntry` into
`isFuncletEntry` and `isEHScopeEntry`, and
`MachineFunction::hasFunclets` into `hasFunclets` and `hasEHScopes`, in
order to distinguish the two different use cases. And this also changes
some uses of the term 'funclet' to 'scope' in `getFuncletMembership` and
change the function name to `getEHScopeMembership` because this function
is not about outlined funclets but about EH scope memberships.
This change is in the same vein as D45559.
Reviewers: majnemer, dschuff
Subscribers: sbc100, jgravelle-google, sunfish, llvm-commits
Differential Revision: https://reviews.llvm.org/D47005
llvm-svn: 333045
diff --git a/llvm/lib/CodeGen/Analysis.cpp b/llvm/lib/CodeGen/Analysis.cpp
index 0731ae5..e7e4bc6 100644
--- a/llvm/lib/CodeGen/Analysis.cpp
+++ b/llvm/lib/CodeGen/Analysis.cpp
@@ -629,26 +629,26 @@
return true;
}
-static void collectFuncletMembers(
- DenseMap<const MachineBasicBlock *, int> &FuncletMembership, int Funclet,
- const MachineBasicBlock *MBB) {
+static void
+collectEHScopeMembers(DenseMap<const MachineBasicBlock *, int> &ScopeMembership,
+ int Scope, const MachineBasicBlock *MBB) {
SmallVector<const MachineBasicBlock *, 16> Worklist = {MBB};
while (!Worklist.empty()) {
const MachineBasicBlock *Visiting = Worklist.pop_back_val();
- // Don't follow blocks which start new funclets.
+ // Don't follow blocks which start new scopes.
if (Visiting->isEHPad() && Visiting != MBB)
continue;
- // Add this MBB to our funclet.
- auto P = FuncletMembership.insert(std::make_pair(Visiting, Funclet));
+ // Add this MBB to our scope.
+ auto P = ScopeMembership.insert(std::make_pair(Visiting, Scope));
// Don't revisit blocks.
if (!P.second) {
- assert(P.first->second == Funclet && "MBB is part of two funclets!");
+ assert(P.first->second == Scope && "MBB is part of two scopes!");
continue;
}
- // Returns are boundaries where funclet transfer can occur, don't follow
+ // Returns are boundaries where scope transfer can occur, don't follow
// successors.
if (Visiting->isReturnBlock())
continue;
@@ -659,25 +659,25 @@
}
DenseMap<const MachineBasicBlock *, int>
-llvm::getFuncletMembership(const MachineFunction &MF) {
- DenseMap<const MachineBasicBlock *, int> FuncletMembership;
+llvm::getEHScopeMembership(const MachineFunction &MF) {
+ DenseMap<const MachineBasicBlock *, int> ScopeMembership;
// We don't have anything to do if there aren't any EH pads.
- if (!MF.hasEHFunclets())
- return FuncletMembership;
+ if (!MF.hasEHScopes())
+ return ScopeMembership;
int EntryBBNumber = MF.front().getNumber();
bool IsSEH = isAsynchronousEHPersonality(
classifyEHPersonality(MF.getFunction().getPersonalityFn()));
const TargetInstrInfo *TII = MF.getSubtarget().getInstrInfo();
- SmallVector<const MachineBasicBlock *, 16> FuncletBlocks;
+ SmallVector<const MachineBasicBlock *, 16> ScopeBlocks;
SmallVector<const MachineBasicBlock *, 16> UnreachableBlocks;
SmallVector<const MachineBasicBlock *, 16> SEHCatchPads;
SmallVector<std::pair<const MachineBasicBlock *, int>, 16> CatchRetSuccessors;
for (const MachineBasicBlock &MBB : MF) {
- if (MBB.isEHFuncletEntry()) {
- FuncletBlocks.push_back(&MBB);
+ if (MBB.isEHScopeEntry()) {
+ ScopeBlocks.push_back(&MBB);
} else if (IsSEH && MBB.isEHPad()) {
SEHCatchPads.push_back(&MBB);
} else if (MBB.pred_empty()) {
@@ -686,8 +686,8 @@
MachineBasicBlock::const_iterator MBBI = MBB.getFirstTerminator();
- // CatchPads are not funclets for SEH so do not consider CatchRet to
- // transfer control to another funclet.
+ // CatchPads are not scopes for SEH so do not consider CatchRet to
+ // transfer control to another scope.
if (MBBI == MBB.end() || MBBI->getOpcode() != TII->getCatchReturnOpcode())
continue;
@@ -700,24 +700,24 @@
}
// We don't have anything to do if there aren't any EH pads.
- if (FuncletBlocks.empty())
- return FuncletMembership;
+ if (ScopeBlocks.empty())
+ return ScopeMembership;
// Identify all the basic blocks reachable from the function entry.
- collectFuncletMembers(FuncletMembership, EntryBBNumber, &MF.front());
- // All blocks not part of a funclet are in the parent function.
+ collectEHScopeMembers(ScopeMembership, EntryBBNumber, &MF.front());
+ // All blocks not part of a scope are in the parent function.
for (const MachineBasicBlock *MBB : UnreachableBlocks)
- collectFuncletMembers(FuncletMembership, EntryBBNumber, MBB);
- // Next, identify all the blocks inside the funclets.
- for (const MachineBasicBlock *MBB : FuncletBlocks)
- collectFuncletMembers(FuncletMembership, MBB->getNumber(), MBB);
- // SEH CatchPads aren't really funclets, handle them separately.
+ collectEHScopeMembers(ScopeMembership, EntryBBNumber, MBB);
+ // Next, identify all the blocks inside the scopes.
+ for (const MachineBasicBlock *MBB : ScopeBlocks)
+ collectEHScopeMembers(ScopeMembership, MBB->getNumber(), MBB);
+ // SEH CatchPads aren't really scopes, handle them separately.
for (const MachineBasicBlock *MBB : SEHCatchPads)
- collectFuncletMembers(FuncletMembership, EntryBBNumber, MBB);
+ collectEHScopeMembers(ScopeMembership, EntryBBNumber, MBB);
// Finally, identify all the targets of a catchret.
for (std::pair<const MachineBasicBlock *, int> CatchRetPair :
CatchRetSuccessors)
- collectFuncletMembers(FuncletMembership, CatchRetPair.second,
+ collectEHScopeMembers(ScopeMembership, CatchRetPair.second,
CatchRetPair.first);
- return FuncletMembership;
+ return ScopeMembership;
}