--- a/js/src/jit/CodeGenerator.cpp
+++ b/js/src/jit/CodeGenerator.cpp
@@ -8324,16 +8324,18 @@ CodeGenerator::generateAsmJS(wasm::FuncO
 #if defined(JS_ION_PERF)
     // Note the end of the inline code and start of the OOL code.
     gen->perfSpewer().noteEndInlineCode(masm);
 #endif
 
     if (!generateOutOfLineCode())
         return false;
 
+    masm.flush();
+
     offsets->end = masm.currentOffset();
 
     MOZ_ASSERT(!masm.failureLabel()->used());
     MOZ_ASSERT(snapshots_.listSize() == 0);
     MOZ_ASSERT(snapshots_.RVATableSize() == 0);
     MOZ_ASSERT(recovers_.size() == 0);
     MOZ_ASSERT(bailouts_.empty());
     MOZ_ASSERT(graph.numConstants() == 0);

--- a/js/src/jit/MacroAssembler.h
+++ b/js/src/jit/MacroAssembler.h
@@ -516,16 +516,19 @@ class MacroAssembler : public MacroAssem
     // operations should be emitted while setting arguments.
     void passABIArg(const MoveOperand& from, MoveOp::Type type);
     inline void passABIArg(Register reg);
     inline void passABIArg(FloatRegister reg, MoveOp::Type type);
 
     template <typename T>
     inline void callWithABI(const T& fun, MoveOp::Type result = MoveOp::GENERAL);
 
+    // Flushes the assembly buffer, on platforms that need it.
+    void flush() PER_SHARED_ARCH;
+
   private:
     // Reinitialize the variables which have to be cleared before making a call
     // with callWithABI.
     void setupABICall();
 
     // Reserve the stack and resolve the arguments move.
     void callWithABIPre(uint32_t* stackAdjust, bool callFromAsmJS = false) PER_ARCH;
 

--- a/js/src/jit/arm/MacroAssembler-arm.cpp
+++ b/js/src/jit/arm/MacroAssembler-arm.cpp
@@ -5063,9 +5063,15 @@ MacroAssembler::branchValueIsNurseryObje
     Label done;
 
     branchTestObject(Assembler::NotEqual, value, cond == Assembler::Equal ? &done : label);
     branchPtrInNurseryRange(cond, value.payloadReg(), temp, label);
 
     bind(&done);
 }
 
+void
+MacroAssembler::flush()
+{
+    Assembler::flush();
+}
+
 //}}} check_macroassembler_style

--- a/js/src/jit/arm64/MacroAssembler-arm64.cpp
+++ b/js/src/jit/arm64/MacroAssembler-arm64.cpp
@@ -718,12 +718,18 @@ MacroAssembler::branchValueIsNurseryObje
     Value start = ObjectValue(*reinterpret_cast<JSObject*>(nursery.start()));
 
     movePtr(ImmWord(-ptrdiff_t(start.asRawBits())), temp);
     addPtr(value.valueReg(), temp);
     branchPtr(cond == Assembler::Equal ? Assembler::Below : Assembler::AboveOrEqual,
               temp, ImmWord(nursery.nurserySize()), label);
 }
 
+void
+MacroAssembler::flush()
+{
+    Assembler::flush();
+}
+
 //}}} check_macroassembler_style
 
 } // namespace jit
 } // namespace js

--- a/js/src/jit/mips-shared/MacroAssembler-mips-shared.cpp
+++ b/js/src/jit/mips-shared/MacroAssembler-mips-shared.cpp
@@ -1286,9 +1286,13 @@ MacroAssembler::branchPtrInNurseryRange(
 
     const Nursery& nursery = GetJitContext()->runtime->gcNursery();
     movePtr(ImmWord(-ptrdiff_t(nursery.start())), SecondScratchReg);
     addPtr(ptr, SecondScratchReg);
     branchPtr(cond == Assembler::Equal ? Assembler::Below : Assembler::AboveOrEqual,
               SecondScratchReg, Imm32(nursery.nurserySize()), label);
 }
 
+void
+MacroAssembler::flush()
+{}
+
 //}}} check_macroassembler_style

--- a/js/src/jit/x86-shared/MacroAssembler-x86-shared.cpp
+++ b/js/src/jit/x86-shared/MacroAssembler-x86-shared.cpp
@@ -586,9 +586,13 @@ MacroAssembler::pushFakeReturnAddress(Re
     Push(scratch);
     use(cl.target());
     uint32_t retAddr = currentOffset();
 
     addCodeLabel(cl);
     return retAddr;
 }
 
+void
+MacroAssembler::flush()
+{}
+
 //}}} check_macroassembler_style