[libcpu][cortex-m33]Added HardFault_Handler to save floating point registers

libcpu/arm/cortex-m33/context_gcc.S

@@ -281,6 +281,12 @@ HardFault_Handler:
     MRS     r0, psp                                 /* get fault context from thread. */
 get_sp_done:
 
+#if defined (__VFP_FP__) && !defined(__SOFTFP__)
+    TST     lr, #0x10                               /* if(!EXC_RETURN[4]) */
+    IT      EQ
+    VSTMDBEQ  r0!, {d8 - d15}                       /* push FPU register s16~s31 */
+#endif
+
     STMFD   r0!, {r4 - r11}                         /* push r4 - r11 register */
 
     LDR     r2,  =rt_trustzone_current_context      /* r2 = &rt_secure_current_context */

libcpu/arm/cortex-m33/context_iar.S

@@ -275,6 +275,13 @@ HardFault_Handler:
     MRS     r0, psp                                 ; get fault context from thread.
 get_sp_done
 
+#if defined ( __ARMVFP__ )
+    TST     lr, #0x10                               ; if(!EXC_RETURN[4])
+    BNE     skip_push_fpu
+    VSTMDB  r0!, {d8 - d15}                         ; push FPU register s16~s31
+skip_push_fpu
+#endif
+
     STMFD   r0!, {r4 - r11}                         ; push r4 - r11 register
 
     LDR     r2,  =rt_trustzone_current_context      ; r2 = &rt_secure_current_context

libcpu/arm/cortex-m33/context_rvds.S

@@ -272,12 +272,17 @@ rt_hw_interrupt_thread_switch PROC
 HardFault_Handler    PROC
 
     ; get current context
-    MRS     r0, msp                 ;get fault context from handler
-    TST     lr, #0x04               ;if(!EXC_RETURN[2])
+    MRS     r0, msp                 ; get fault context from handler
+    TST     lr, #0x04               ; if(!EXC_RETURN[2])
     BEQ     get_sp_done
-    MRS     r0, psp                 ;get fault context from thread
+    MRS     r0, psp                 ; get fault context from thread
 get_sp_done
 
+    IF      {FPU} != "SoftVFP"
+    TST     lr, #0x10               ; if(!EXC_RETURN[4])
+    VSTMFDEQ r0!, {d8 - d15}        ; push FPU register s16~s31
+    ENDIF
+
     STMFD   r0!, {r4 - r11}         ; push r4 - r11 register
 
     LDR     r2,  =rt_trustzone_current_context      ; r2 = &rt_secure_current_context