Enable access to FPU registers only if FPU is enabled

portable/GCC/ARM_CR5/portASM.S

@@ -64,6 +64,7 @@
 	LDR		R1, [R2]
 	PUSH	{R1}
 
+	#ifdef __ARM_FP
 	/* Does the task have a floating point context that needs saving?  If
 	ulPortTaskHasFPUContext is 0 then no. */
 	LDR		R2, ulPortTaskHasFPUContextConst
@@ -78,6 +79,7 @@
 
 	/* Save ulPortTaskHasFPUContext itself. */
 	PUSH	{R3}
+	#endif /* __ARM_FP */
 
 	/* Save the stack pointer in the TCB. */
 	LDR		R0, pxCurrentTCBConst
@@ -95,6 +97,7 @@
 	LDR		R1, [R0]
 	LDR		SP, [R1]
 
+	#ifdef __ARM_FP
 	/* Is there a floating point context to restore?  If the restored
 	ulPortTaskHasFPUContext is zero then no. */
 	LDR		R0, ulPortTaskHasFPUContextConst
@@ -107,6 +110,7 @@
 	/*VPOPNE	{D16-D31}*/
 	VPOPNE	{D0-D15}
 	VMSRNE  FPSCR, R0
+	#endif /* __ARM_FP */
 
 	/* Restore the critical section nesting depth. */
 	LDR		R0, ulCriticalNestingConst
@@ -279,22 +283,27 @@ switch_before_exit:
  * FPU registers to be saved on interrupt entry their IRQ handler must be
  * called vApplicationIRQHandler().
  *****************************************************************************/
-
 .align 4
 .weak vApplicationIRQHandler
 .type vApplicationIRQHandler, %function
 vApplicationIRQHandler:
+
 	PUSH	{LR}
+
+	#ifdef __ARM_FP
 	FMRX	R1,  FPSCR
 	VPUSH	{D0-D15}
 	PUSH	{R1}
+	#endif /* __ARM_FP */
 
 	LDR		r1, vApplicationFPUSafeIRQHandlerConst
 	BLX		r1
 
+	#ifdef __ARM_FP
 	POP		{R0}
 	VPOP	{D0-D15}
 	VMSR	FPSCR, R0
+	#endif /* __ARM_FP */
 
 	POP {PC}