[WebAssembly] Fix unwind mismatch stat computation
Summary:
There was a bug when computing the number of unwind destination
mismatches in CFGStackify. When there are many mismatched calls that
share the same (original) destination BB, they have to be counted
separately.
This also fixes a typo and runs `fixUnwindMismatches` only when the wasm
exception handling is enabled. This is to prevent unnecessary
computations and does not change behavior.
Reviewers: dschuff
Subscribers: sbc100, jgravelle-google, hiraditya, sunfish, llvm-commits
Tags: #llvm
Differential Revision: https://reviews.llvm.org/D68552
llvm-svn: 373975
diff --git a/llvm/lib/Target/WebAssembly/WebAssemblyCFGStackify.cpp b/llvm/lib/Target/WebAssembly/WebAssemblyCFGStackify.cpp
index 6b20946..d2a3557 100644
--- a/llvm/lib/Target/WebAssembly/WebAssemblyCFGStackify.cpp
+++ b/llvm/lib/Target/WebAssembly/WebAssemblyCFGStackify.cpp
@@ -848,7 +848,7 @@
SmallVector<const MachineBasicBlock *, 8> EHPadStack;
// Range of intructions to be wrapped in a new nested try/catch
using TryRange = std::pair<MachineInstr *, MachineInstr *>;
- // In original CFG, <unwind destionation BB, a vector of try ranges>
+ // In original CFG, <unwind destination BB, a vector of try ranges>
DenseMap<MachineBasicBlock *, SmallVector<TryRange, 4>> UnwindDestToTryRanges;
// In new CFG, <destination to branch to, a vector of try ranges>
DenseMap<MachineBasicBlock *, SmallVector<TryRange, 4>> BrDestToTryRanges;
@@ -985,7 +985,7 @@
// ...
// cont:
for (auto &P : UnwindDestToTryRanges) {
- NumUnwindMismatches++;
+ NumUnwindMismatches += P.second.size();
// This means the destination is the appendix BB, which was separately
// handled above.
@@ -1300,7 +1300,9 @@
}
}
// Fix mismatches in unwind destinations induced by linearizing the code.
- fixUnwindMismatches(MF);
+ if (MCAI->getExceptionHandlingType() == ExceptionHandling::Wasm &&
+ MF.getFunction().hasPersonalityFn())
+ fixUnwindMismatches(MF);
}
void WebAssemblyCFGStackify::rewriteDepthImmediates(MachineFunction &MF) {