Diff: targets/TARGET_STM/TARGET_STM32F0/TARGET_NUCLEO_F091RC/device/TOOLCHAIN_GCC_ARM/startup_stm32f091xc.S

Revision:

180:96ed750bd169

Parent:

150:02e0a0aed4ec

--- a/targets/TARGET_STM/TARGET_STM32F0/TARGET_NUCLEO_F091RC/device/TOOLCHAIN_GCC_ARM/startup_stm32f091xc.S	Thu Dec 07 14:01:42 2017 +0000
+++ b/targets/TARGET_STM/TARGET_STM32F0/TARGET_NUCLEO_F091RC/device/TOOLCHAIN_GCC_ARM/startup_stm32f091xc.S	Wed Jan 17 15:23:54 2018 +0000
@@ -2,9 +2,7 @@
   ******************************************************************************
   * @file      startup_stm32f091xc.s
   * @author    MCD Application Team
-  * @version   V2.1.0
-  * @date      03-Oct-2014
-  * @brief     STM32F091xC devices vector table for Atollic TrueSTUDIO toolchain.
+  * @brief     STM32F091xC devices vector table for GCC toolchain.
   *            This module performs:
   *                - Set the initial SP
   *                - Set the initial PC == Reset_Handler,
@@ -55,6 +53,10 @@
 .word _sdata
 /* end address for the .data section. defined in linker script */
 .word _edata
+/* start address for the .bss section. defined in linker script */
+.word _sbss
+/* end address for the .bss section. defined in linker script */
+.word _ebss
 
   .section .text.Reset_Handler
   .weak Reset_Handler
@@ -64,21 +66,35 @@
   mov   sp, r0          /* set stack pointer */
 
 /* Copy the data segment initializers from flash to SRAM */
-  movs r1, #0
+  ldr r0, =_sdata
+  ldr r1, =_edata
+  ldr r2, =_sidata
+  movs r3, #0
   b LoopCopyDataInit
 
 CopyDataInit:
-  ldr r3, =_sidata
-  ldr r3, [r3, r1]
-  str r3, [r0, r1]
-  adds r1, r1, #4
+  ldr r4, [r2, r3]
+  str r4, [r0, r3]
+  adds r3, r3, #4
 
 LoopCopyDataInit:
-  ldr r0, =_sdata
-  ldr r3, =_edata
-  adds r2, r0, r1
-  cmp r2, r3
+  adds r4, r0, r3
+  cmp r4, r1
   bcc CopyDataInit
+  
+/* Zero fill the bss segment. */
+  ldr r2, =_sbss
+  ldr r4, =_ebss
+  movs r3, #0
+  b LoopFillZerobss
+
+FillZerobss:
+  str  r3, [r2]
+  adds r2, r2, #4
+
+LoopFillZerobss:
+  cmp r2, r4
+  bcc FillZerobss
 
 /* Call the clock system intitialization function.*/
     bl  SystemInit