From c309112b8a9b3d1891ad0ad4e83518495aa5de95 Mon Sep 17 00:00:00 2001
From: Felipe Neves <felipe.neves@espressif.com>
Date: Mon, 6 Jan 2020 17:01:53 -0300
Subject: [PATCH] expression_with_stack:make stack overflow detection
 watchpoint optional

---
 .../xtensa/expression_with_stack_xtensa.c     | 19 +++++++++++++++++++
 .../xtensa/expression_with_stack_xtensa_asm.S |  4 ++++
 2 files changed, 23 insertions(+)

diff --git a/components/xtensa/expression_with_stack_xtensa.c b/components/xtensa/expression_with_stack_xtensa.c
index 6f9cf4ca3c..74829d7e8b 100644
--- a/components/xtensa/expression_with_stack_xtensa.c
+++ b/components/xtensa/expression_with_stack_xtensa.c
@@ -1,10 +1,26 @@
+// Copyright 2015-2019 Espressif Systems (Shanghai) PTE LTD
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//     http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
 #include <esp_expression_with_stack.h>
 #include <freertos/xtensa_rtos.h>
 #include <freertos/xtensa_context.h>
 
 StackType_t * esp_switch_stack_setup(StackType_t *stack, size_t stack_size)
 {
+#if CONFIG_FREERTOS_WATCHPOINT_END_OF_STACK
     int watchpoint_place = (((int)stack + 31) & ~31);
+#endif    
     StackType_t *top_of_stack =  (StackType_t *)&stack[0] +                  
             ((stack_size * sizeof(StackType_t)) / sizeof(StackType_t));
 
@@ -18,6 +34,9 @@ StackType_t * esp_switch_stack_setup(StackType_t *stack, size_t stack_size)
     frame->a0 = 0;
     frame->a1 = (UBaseType_t)top_of_stack;
 
+#if CONFIG_FREERTOS_WATCHPOINT_END_OF_STACK
     esp_set_watchpoint(2, (char*)watchpoint_place, 32, ESP_WATCHPOINT_STORE);    
+#endif
+
     return top_of_stack;           
 }
\ No newline at end of file
diff --git a/components/xtensa/expression_with_stack_xtensa_asm.S b/components/xtensa/expression_with_stack_xtensa_asm.S
index 106eb6f9c4..f868131ba0 100644
--- a/components/xtensa/expression_with_stack_xtensa_asm.S
+++ b/components/xtensa/expression_with_stack_xtensa_asm.S
@@ -46,9 +46,13 @@ esp_switch_stack_exit:
 
     #ifndef __XTENSA_CALL0_ABI__
         entry   sp, 0x10
+
+#if CONFIG_FREERTOS_WATCHPOINT_END_OF_STACK        
         movi a6, 2
         movi a4, esp_clear_watchpoint
         callx4 a4 /* clear the watchpoint before releasing stack */
+#endif
+
         l32i a4, a2, 0  /* recover the original task stack */
         mov a1, a4      /* put it on sp register again */
         retw