diff --git a/js/src/nanojit/LIR.cpp b/js/src/nanojit/LIR.cpp
index 758a326b8d4..d2cc3b5246b 100755
--- a/js/src/nanojit/LIR.cpp
+++ b/js/src/nanojit/LIR.cpp
@@ -1544,12 +1544,16 @@ namespace nanojit
 		}
 		else {
 			if (ref->isCall()) {
+#if !defined NANOJIT_64BIT
 				if (ref->isop(LIR_callh)) {
 					// we've presumably seen the other half already
 					ref = ref->oprnd1();
 				} else {
+#endif
 					copyName(ref, _functions[ref->fid()]._name, funccounts.add(ref->fid()));
+#if !defined NANOJIT_64BIT
 				}
+#endif
 			} else {
                 NanoAssert(ref->opcode() < sizeof(lirNames) / sizeof(lirNames[0]));
 				copyName(ref, lirNames[ref->opcode()], lircounts.add(ref->opcode()));
diff --git a/js/src/nanojit/Nativei386.cpp b/js/src/nanojit/Nativei386.cpp
index 3cac5679526..62bd1a1ee9c 100644
--- a/js/src/nanojit/Nativei386.cpp
+++ b/js/src/nanojit/Nativei386.cpp
@@ -878,8 +878,15 @@ namespace nanojit
 			Register ra;
 
 			// if this is last use of lhs in reg, we can re-use result reg
-			if (rA == 0 || (ra = rA->reg) == UnknownReg)
+			if (rA == 0 || (ra = rA->reg) == UnknownReg) {
 				ra = findSpecificRegFor(lhs, rr);
+			} else if ((rmask(ra) & XmmRegs) == 0) {
+				/* We need this case on AMD64, because it's possible that 
+				 * an earlier instruction has done a quadword load and reserved a 
+				 * GPR.  If so, ask for a new register.
+				 */
+				ra = findRegFor(lhs, XmmRegs);
+			}
 			// else, rA already has a register assigned.
 
 			static const AVMPLUS_ALIGN16(uint32_t) negateMask[] = {0,0x80000000,0,0};
@@ -975,8 +982,15 @@ namespace nanojit
 			Register ra;
 
 			// if this is last use of lhs in reg, we can re-use result reg
-			if (rA == 0 || (ra = rA->reg) == UnknownReg)
+			if (rA == 0 || (ra = rA->reg) == UnknownReg) {
 				ra = findSpecificRegFor(lhs, rr);
+			} else if ((rmask(ra) & XmmRegs) == 0) {
+				/* We need this case on AMD64, because it's possible that 
+				 * an earlier instruction has done a quadword load and reserved a 
+				 * GPR.  If so, ask for a new register.
+				 */
+				ra = findRegFor(lhs, XmmRegs);
+			}
 			// else, rA already has a register assigned.
 
 			if (lhs == rhs)
diff --git a/js/src/trace-test.js b/js/src/trace-test.js
index 5e244358766..68f2c6401d0 100644
--- a/js/src/trace-test.js
+++ b/js/src/trace-test.js
@@ -1178,7 +1178,7 @@ testNegZero1.name = 'testNegZero1';
 testNegZero1Helper(1);
 test(testNegZero1);
 
-/* No test case, just make sure this doesn't assert. */
+// No test case, just make sure this doesn't assert. 
 function testNegZero2() {
     var z = 0;
     for (let j = 0; j < 5; ++j) { ({p: (-z)}); }