When searching for new bytecode instr for a post-op bailout, follow unconditional branches.

Author: Cellule

lib/Backend/GlobOptBailOut.cpp

@@ -1372,24 +1372,10 @@ GlobOpt::MayNeedBailOnImplicitCall(IR::Instr const * instr, Value const * src1Va
 void
 GlobOpt::GenerateBailAfterOperation(IR::Instr * *const pInstr, IR::BailOutKind kind)
 {
-    Assert(pInstr);
+    Assert(pInstr && *pInstr);
 
     IR::Instr* instr = *pInstr;
-    Assert(instr);
-
-    IR::Instr * nextInstr = instr->GetNextRealInstrOrLabel();
-    uint32 currentOffset = instr->GetByteCodeOffset();
-    while (nextInstr->GetByteCodeOffset() == Js::Constants::NoByteCodeOffset ||
-        nextInstr->GetByteCodeOffset() == currentOffset)
-    {
-        nextInstr = nextInstr->GetNextRealInstrOrLabel();
-    }
-    // This can happen due to break block removal
-    while (nextInstr->GetByteCodeOffset() == Js::Constants::NoByteCodeOffset ||
-        nextInstr->GetByteCodeOffset() < currentOffset)
-    {
-        nextInstr = nextInstr->GetNextRealInstrOrLabel();
-    }
+    IR::Instr * nextInstr = instr->GetNextByteCodeInstr();
     IR::Instr * bailOutInstr = instr->ConvertToBailOutInstr(nextInstr, kind);
     if (this->currentBlock->GetLastInstr() == instr)
     {

lib/Backend/IR.cpp

@@ -2704,6 +2704,35 @@ Instr::GetNextBranchOrLabel() const
     return instr;
 }
 
+IR::Instr *
+Instr::GetNextByteCodeInstr() const
+{
+    IR::Instr * nextInstr = GetNextRealInstrOrLabel();
+    uint32 currentOffset = GetByteCodeOffset();
+    const auto getNext = [](IR::Instr* nextInstr) -> IR::Instr*
+    {
+        if (nextInstr->IsBranchInstr())
+        {
+            IR::BranchInstr* branchInstr = nextInstr->AsBranchInstr();
+            AssertMsg(branchInstr->IsUnconditional(), "We can't know which branch to take on a conditionnal branch");
+            return branchInstr->GetTarget();
+        }
+        return nextInstr->GetNextRealInstrOrLabel();
+    };
+    while (nextInstr->GetByteCodeOffset() == Js::Constants::NoByteCodeOffset ||
+        nextInstr->GetByteCodeOffset() == currentOffset)
+    {
+        nextInstr = getNext(nextInstr);
+    }
+    // This can happen due to break block removal
+    while (nextInstr->GetByteCodeOffset() == Js::Constants::NoByteCodeOffset ||
+        nextInstr->GetByteCodeOffset() < currentOffset)
+    {
+        nextInstr = getNext(nextInstr);
+    }
+    return nextInstr;
+}
+
 ///----------------------------------------------------------------------------
 ///
 /// Instr::GetPrevRealInstr

lib/Backend/IR.h

@@ -288,6 +288,7 @@ class Instr
     IR::Instr *     GetNextRealInstr() const;
     IR::Instr *     GetNextRealInstrOrLabel() const;
     IR::Instr *     GetNextBranchOrLabel() const;
+    IR::Instr *     GetNextByteCodeInstr() const;
     IR::Instr *     GetPrevRealInstr() const;
     IR::Instr *     GetPrevRealInstrOrLabel() const;
     IR::LabelInstr *GetPrevLabelInstr() const;