diff --git a/js/src/jit/mips/Simulator-mips.cpp b/js/src/jit/mips/Simulator-mips.cpp
index f6c4a2b7327..cfe6efb2c88 100644
--- a/js/src/jit/mips/Simulator-mips.cpp
+++ b/js/src/jit/mips/Simulator-mips.cpp
@@ -497,9 +497,9 @@ Simulator::Create()
     if (!sim)
         return nullptr;
 
-    if (!sim->icache_.init()) {
+    if (!sim->init()) {
         js_delete(sim);
-        return false;
+        return nullptr;
     }
 
     if (getenv("MIPS_SIM_ICACHE_CHECKS"))
@@ -1214,16 +1214,11 @@ Simulator::Simulator()
     // Set up simulator support first. Some of this information is needed to
     // setup the architecture state.
 
-    // Allocate 2MB for the stack. Note that we will only use 1MB, see below.
-    static const size_t stackSize = 2 * 1024 * 1024;
-    stack_ = static_cast<char*>(js_malloc(stackSize));
-    if (!stack_) {
-        MOZ_ReportAssertionFailure("[unhandlable oom] Simulator stack", __FILE__, __LINE__);
-        MOZ_CRASH();
-    }
-    // Leave a safety margin of 1MB to prevent overrunning the stack when
-    // pushing values (total stack size is 2MB).
-    stackLimit_ = reinterpret_cast<uintptr_t>(stack_) + 1024 * 1024;
+    // Note, allocation and anything that depends on allocated memory is
+    // deferred until init(), in order to handle OOM properly.
+
+    stack_ = nullptr;
+    stackLimit_ = 0;
     pc_modified_ = false;
     icount_ = 0;
     break_count_ = 0;
@@ -1241,10 +1236,6 @@ Simulator::Simulator()
     }
     FCSR_ = 0;
 
-    // The sp is initialized to point to the bottom (high address) of the
-    // allocated stack area. To be safe in potential stack underflows we leave
-    // some buffer below.
-    registers_[sp] = reinterpret_cast<int32_t>(stack_) + stackSize - 64;
     // The ra and pc are initialized to a known bad value that will cause an
     // access violation if the simulator ever tries to execute it.
     registers_[pc] = bad_ra;
@@ -1258,6 +1249,30 @@ Simulator::Simulator()
     redirection_ = nullptr;
 }
 
+bool
+Simulator::init()
+{
+    if (!icache_.init())
+        return false;
+
+    // Allocate 2MB for the stack. Note that we will only use 1MB, see below.
+    static const size_t stackSize = 2 * 1024 * 1024;
+    stack_ = static_cast<char*>(js_malloc(stackSize));
+    if (!stack_)
+        return false;
+
+    // Leave a safety margin of 1MB to prevent overrunning the stack when
+    // pushing values (total stack size is 2MB).
+    stackLimit_ = reinterpret_cast<uintptr_t>(stack_) + 1024 * 1024;
+
+    // The sp is initialized to point to the bottom (high address) of the
+    // allocated stack area. To be safe in potential stack underflows we leave
+    // some buffer below.
+    registers_[sp] = reinterpret_cast<int32_t>(stack_) + stackSize - 64;
+
+    return true;
+}
+
 // When the generated code calls an external reference we need to catch that in
 // the simulator.  The external reference will be a function compiled for the
 // host architecture.  We need to call that function instead of trying to
diff --git a/js/src/jit/mips/Simulator-mips.h b/js/src/jit/mips/Simulator-mips.h
index d9e1d0eb1d2..4c98bce14fd 100644
--- a/js/src/jit/mips/Simulator-mips.h
+++ b/js/src/jit/mips/Simulator-mips.h
@@ -137,7 +137,9 @@ class Simulator {
         kNumFPURegisters
     };
 
+    // Returns nullptr on OOM.
     static Simulator *Create();
+
     static void Destroy(Simulator *simulator);
 
     // Constructor/destructor are for internal use only; use the static methods above.
@@ -224,6 +226,8 @@ class Simulator {
         Unpredictable = 0xbadbeaf
     };
 
+    bool init();
+
     // Unsupported instructions use Format to print an error and stop execution.
     void format(SimInstruction* instr, const char* format);