1 files changed, 63 insertions, 1 deletions

diff --git a/js/src/wasm/WasmFrameIter.cpp b/js/src/wasm/WasmFrameIter.cpp
index 90555720da..e9f27bbda0 100644
--- a/js/src/wasm/WasmFrameIter.cpp
+++ b/js/src/wasm/WasmFrameIter.cpp
@@ -26,6 +26,7 @@
 #include "wasm/WasmDebugFrame.h"
 #include "wasm/WasmInstance.h"
 #include "wasm/WasmInstanceData.h"
+#include "wasm/WasmPI.h"
 #include "wasm/WasmStubs.h"
 
 #include "jit/MacroAssembler-inl.h"
@@ -65,7 +66,8 @@ WasmFrameIter::WasmFrameIter(JitActivation* activation, wasm::Frame* fp)
       unwind_(Unwind::False),
       unwoundAddressOfReturnAddress_(nullptr),
       resumePCinCurrentFrame_(nullptr),
-      failedUnwindSignatureMismatch_(false) {
+      failedUnwindSignatureMismatch_(false),
+      stackSwitched_(false) {
   MOZ_ASSERT(fp_);
   instance_ = GetNearestEffectiveInstance(fp_);
 
@@ -88,6 +90,19 @@ WasmFrameIter::WasmFrameIter(JitActivation* activation, wasm::Frame* fp)
     lineOrBytecode_ = trapData.bytecodeOffset;
     failedUnwindSignatureMismatch_ = trapData.failedUnwindSignatureMismatch;
 
+#ifdef ENABLE_WASM_TAIL_CALLS
+    // The debugEnabled() relies on valid value of resumePCinCurrentFrame_
+    // to identify DebugFrame. Normally this field is updated at popFrame().
+    // The only case when this can happend is during IndirectCallBadSig
+    // trapping and stack unwinding. The top frame will never be at ReturnStub
+    // callsite, except during IndirectCallBadSig unwinding.
+    const CallSite* site = code_->lookupCallSite(unwoundPC);
+    if (site && site->kind() == CallSite::ReturnStub) {
+      MOZ_ASSERT(trapData.trap == Trap::IndirectCallBadSig);
+      resumePCinCurrentFrame_ = (uint8_t*)unwoundPC;
+    }
+#endif
+
     MOZ_ASSERT(!done());
     return;
   }
@@ -102,6 +117,39 @@ WasmFrameIter::WasmFrameIter(JitActivation* activation, wasm::Frame* fp)
   MOZ_ASSERT(!done() || unwoundCallerFP_);
 }
 
+WasmFrameIter::WasmFrameIter(FrameWithInstances* fp, void* returnAddress)
+    : activation_(nullptr),
+      code_(nullptr),
+      codeRange_(nullptr),
+      lineOrBytecode_(0),
+      fp_(fp),
+      instance_(fp->calleeInstance()),
+      unwoundCallerFP_(nullptr),
+      unwind_(Unwind::False),
+      unwoundAddressOfReturnAddress_(nullptr),
+      resumePCinCurrentFrame_((uint8_t*)returnAddress),
+      failedUnwindSignatureMismatch_(false),
+      stackSwitched_(false) {
+  // Specialized implementation to avoid popFrame() interation.
+  // It is expected that the iterator starts at a callsite that is in
+  // the function body and has instance reference.
+  code_ = LookupCode(returnAddress, &codeRange_);
+  MOZ_ASSERT(code_ && codeRange_ && codeRange_->kind() == CodeRange::Function);
+
+  const CallSite* callsite = code_->lookupCallSite(returnAddress);
+  MOZ_ASSERT(callsite && callsite->mightBeCrossInstance());
+
+#ifdef ENABLE_WASM_JSPI
+  stackSwitched_ = callsite->isStackSwitch();
+#endif
+
+  MOZ_ASSERT(code_ == &instance_->code());
+  lineOrBytecode_ = callsite->lineOrBytecode();
+  failedUnwindSignatureMismatch_ = false;
+
+  MOZ_ASSERT(!done());
+}
+
 bool WasmFrameIter::done() const {
   MOZ_ASSERT(!!fp_ == !!code_);
   MOZ_ASSERT(!!fp_ == !!codeRange_);
@@ -145,6 +193,9 @@ static inline void AssertDirectJitCall(const void* fp) {
 void WasmFrameIter::popFrame() {
   uint8_t* returnAddress = fp_->returnAddress();
   code_ = LookupCode(returnAddress, &codeRange_);
+#ifdef ENABLE_WASM_JSPI
+  stackSwitched_ = false;
+#endif
 
   if (!code_) {
     // This is a direct call from the jit into the wasm function's body. The
@@ -241,6 +292,13 @@ void WasmFrameIter::popFrame() {
     instance_ = ExtractCallerInstanceFromFrameWithInstances(prevFP);
   }
 
+#ifdef ENABLE_WASM_JSPI
+  stackSwitched_ = callsite->isStackSwitch();
+  if (stackSwitched_ && unwind_ == Unwind::True) {
+    wasm::UnwindStackSwitch(activation_->cx());
+  }
+#endif
+
   MOZ_ASSERT(code_ == &instance()->code());
   lineOrBytecode_ = callsite->lineOrBytecode();
   failedUnwindSignatureMismatch_ = false;
@@ -1811,6 +1869,10 @@ static const char* ThunkedNativeToDescription(SymbolicAddress func) {
     return "call to native " #op " builtin (in wasm)";
       FOR_EACH_BUILTIN_MODULE_FUNC(VISIT_BUILTIN_FUNC)
 #undef VISIT_BUILTIN_FUNC
+#ifdef ENABLE_WASM_JSPI
+    case SymbolicAddress::UpdateSuspenderState:
+      return "call to native update suspender state util";
+#endif
 #ifdef WASM_CODEGEN_DEBUG
     case SymbolicAddress::PrintI32:
     case SymbolicAddress::PrintPtr: