LLVM 20.0.0git
WebAssemblySortRegion.cpp
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4
5using namespace llvm;
6using namespace WebAssembly;
7
8namespace llvm {
9namespace WebAssembly {
10template <>
12 return true;
13}
14} // end namespace WebAssembly
15} // end namespace llvm
16
18 const auto *ML = MLI.getLoopFor(MBB);
19 const auto *WE = WEI.getExceptionFor(MBB);
20 if (!ML && !WE)
21 return nullptr;
22 // We determine subregion relationship by domination of their headers, i.e.,
23 // if region A's header dominates region B's header, B is a subregion of A.
24 // WebAssemblyException contains BBs in all its subregions (loops or
25 // exceptions), but MachineLoop may not, because MachineLoop does not
26 // contain BBs that don't have a path to its header even if they are
27 // dominated by its header. So here we should use
28 // WE->contains(ML->getHeader()), but not ML->contains(WE->getHeader()).
29 if ((ML && !WE) || (ML && WE && WE->contains(ML->getHeader()))) {
30 // If the smallest region containing MBB is a loop
31 if (LoopMap.count(ML))
32 return LoopMap[ML].get();
33 LoopMap[ML] = std::make_unique<ConcreteSortRegion<MachineLoop>>(ML);
34 return LoopMap[ML].get();
35 } else {
36 // If the smallest region containing MBB is an exception
37 if (ExceptionMap.count(WE))
38 return ExceptionMap[WE].get();
39 ExceptionMap[WE] =
40 std::make_unique<ConcreteSortRegion<WebAssemblyException>>(WE);
41 return ExceptionMap[WE].get();
42 }
43}
44
46 if (R->isLoop())
47 return getBottom(MLI.getLoopFor(R->getHeader()));
48 else
49 return getBottom(WEI.getExceptionFor(R->getHeader()));
50}
51
53 MachineBasicBlock *Bottom = ML->getHeader();
54 for (MachineBasicBlock *MBB : ML->blocks()) {
55 if (MBB->getNumber() > Bottom->getNumber())
56 Bottom = MBB;
57 // MachineLoop does not contain all BBs dominated by its header. BBs that
58 // don't have a path back to the loop header aren't included. But for the
59 // purpose of CFG sorting and stackification, we need a bottom BB among all
60 // BBs that are dominated by the loop header. So we check if there is any
61 // WebAssemblyException contained in this loop, and computes the most bottom
62 // BB of them all.
63 if (MBB->isEHPad()) {
65 if (ExBottom->getNumber() > Bottom->getNumber())
66 Bottom = ExBottom;
67 }
68 }
69 return Bottom;
70}
71
73 MachineBasicBlock *Bottom = WE->getHeader();
74 for (MachineBasicBlock *MBB : WE->blocks())
75 if (MBB->getNumber() > Bottom->getNumber())
76 Bottom = MBB;
77 return Bottom;
78}
MachineBasicBlock & MBB
This file implements WebAssemblyException information analysis.
This file implements regions used in CFGSort and CFGStackify.
LoopT * getLoopFor(const BlockT *BB) const
Return the inner most loop that BB lives in.
bool isEHPad() const
Returns true if the block is a landing pad.
int getNumber() const
MachineBasicBlocks are uniquely numbered at the function level, unless they're not in a MachineFuncti...
WebAssemblyException * getExceptionFor(const MachineBasicBlock *MBB) const
iterator_range< block_iterator > blocks() const
MachineBasicBlock * getHeader() const
const SortRegion * getRegionFor(const MachineBasicBlock *MBB)
MachineBasicBlock * getBottom(const SortRegion *R)
This is an optimization pass for GlobalISel generic memory operations.
Definition: AddressRanges.h:18
decltype(auto) get(const PointerIntPair< PointerTy, IntBits, IntType, PtrTraits, Info > &Pair)