Bug 1173908 - Fix an MSVC warning about negating an unsigned integer; r=nbp

--HG--
extra : rebase_source : 37e9f775cebad5269c7328c6bc29148b31a0d10b

js/src/jit/MacroAssembler-inl.h

@@ -28,8 +28,9 @@ MacroAssembler::setFramePushed(uint32_t framePushed)
 }
 
 void
-MacroAssembler::adjustFrame(int value)
+MacroAssembler::adjustFrame(int32_t value)
 {
+    MOZ_ASSERT_IF(value < 0, framePushed_ >= -value);
     setFramePushed(framePushed_ + value);
 }
 
@@ -37,7 +38,8 @@ void
 MacroAssembler::implicitPop(uint32_t bytes)
 {
     MOZ_ASSERT(bytes % sizeof(intptr_t) == 0);
-    adjustFrame(-bytes);
+    MOZ_ASSERT(bytes <= INT32_MAX);
+    adjustFrame(-int32_t(bytes));
 }
 
 // ===============================================================

js/src/jit/MacroAssembler.h

@@ -280,7 +280,7 @@ class MacroAssembler : public MacroAssemblerSpecific
 
     inline uint32_t framePushed() const;
     inline void setFramePushed(uint32_t framePushed);
-    inline void adjustFrame(int value);
+    inline void adjustFrame(int32_t value);
 
     // Adjust the frame, to account for implicit modification of the stack
     // pointer, such that callee can remove arguments on the behalf of the