add IAR warning flags to cmake build and fix them

2 files changed, 21 insertions, 24 deletions

diff --git a/src/common/tusb_fifo.c b/src/common/tusb_fifo.c
index 9f188f296..8bd79e56d 100644
--- a/src/common/tusb_fifo.c
+++ b/src/common/tusb_fifo.c
@@ -30,11 +30,6 @@
 
 #define TU_FIFO_DBG 0
 
-// Suppress IAR warning
-// Warning[Pa082]: undefined behavior: the order of volatile accesses is undefined in this statement
-#if defined(__ICCARM__)
-  #pragma diag_suppress = Pa082
-#endif
 
 #if OSAL_MUTEX_REQUIRED
 
@@ -496,7 +491,9 @@ uint16_t tu_fifo_peek_n_access_mode(tu_fifo_t *f, void *p_buffer, uint16_t n, ui
 // Read n items without removing it from the FIFO, correct read pointer if overflowed
 uint16_t tu_fifo_peek_n(tu_fifo_t *f, void *p_buffer, uint16_t n) {
   ff_lock(f->mutex_rd);
-  const uint16_t ret = tu_fifo_peek_n_access_mode(f, p_buffer, n, f->wr_idx, f->rd_idx, NULL);
+  const uint16_t wr_idx = f->wr_idx;
+  const uint16_t rd_idx = f->rd_idx;
+  const uint16_t ret = tu_fifo_peek_n_access_mode(f, p_buffer, n, wr_idx, rd_idx, NULL);
   ff_unlock(f->mutex_rd);
   return ret;
 }
@@ -506,7 +503,8 @@ uint16_t tu_fifo_read_n_access_mode(tu_fifo_t *f, void *buffer, uint16_t n, cons
   ff_lock(f->mutex_rd);
 
   // Peek the data: f->rd_idx might get modified in case of an overflow so we can not use a local variable
-  n         = tu_fifo_peek_n_access_mode(f, buffer, n, f->wr_idx, f->rd_idx, access_mode);
+  const uint16_t wr_idx = f->wr_idx;
+  n         = tu_fifo_peek_n_access_mode(f, buffer, n, wr_idx, f->rd_idx, access_mode);
   f->rd_idx = advance_index(f->depth, f->rd_idx, n);
 
   ff_unlock(f->mutex_rd);
@@ -633,7 +631,8 @@ static bool ff_peek_local(tu_fifo_t *f, void *buf, uint16_t wr_idx, uint16_t rd_
 bool tu_fifo_read(tu_fifo_t *f, void *buffer) {
   // Peek the data
   // f->rd_idx might get modified in case of an overflow so we can not use a local variable
-  const bool ret = ff_peek_local(f, buffer, f->wr_idx, f->rd_idx);
+  const uint16_t wr_idx = f->wr_idx;
+  const bool ret = ff_peek_local(f, buffer, wr_idx, f->rd_idx);
   if (ret) {
     ff_lock(f->mutex_rd);
     f->rd_idx = advance_index(f->depth, f->rd_idx, 1);
@@ -645,7 +644,9 @@ bool tu_fifo_read(tu_fifo_t *f, void *buffer) {
 
 // Read one item without removing it from the FIFO, correct read index if overflowed
 bool tu_fifo_peek(tu_fifo_t *f, void *p_buffer) {
-  return ff_peek_local(f, p_buffer, f->wr_idx, f->rd_idx);
+  const uint16_t wr_idx = f->wr_idx;
+  const uint16_t rd_idx = f->rd_idx;
+  return ff_peek_local(f, p_buffer, wr_idx, rd_idx);
 }
 
 // Write one element into the buffer
diff --git a/src/common/tusb_fifo.h b/src/common/tusb_fifo.h
index a3829e38e..b31a0802e 100644
--- a/src/common/tusb_fifo.h
+++ b/src/common/tusb_fifo.h
@@ -120,9 +120,9 @@ typedef struct {
   uint8_t *buffer;              // buffer pointer
   uint16_t depth;               // max items
   bool     overwritable;        // overwritable when full
-  // 1 byte padding  here
+  // 1 byte padding here
 
-  volatile uint16_t wr_idx;     // write index TODO maybe can drop volatile
+  volatile uint16_t wr_idx;     // write index
   volatile uint16_t rd_idx;     // read index
 
 #if OSAL_MUTEX_REQUIRED
@@ -289,30 +289,26 @@ TU_ATTR_ALWAYS_INLINE static inline bool tu_fifo_empty(const tu_fifo_t *f) {
   return wr_idx == rd_idx;
 }
 
-// Suppress IAR warning
-// Warning[Pa082]: undefined behavior: the order of volatile accesses is undefined in this statement
-#if defined(__ICCARM__)
-#pragma diag_suppress = Pa082
-#endif
-
 // return number of items in fifo, capped to fifo's depth
 TU_ATTR_ALWAYS_INLINE static inline uint16_t tu_fifo_count(const tu_fifo_t *f) {
-  return tu_min16(tu_ff_overflow_count(f->depth, f->wr_idx, f->rd_idx), f->depth);
+  const uint16_t wr_idx = f->wr_idx;
+  const uint16_t rd_idx = f->rd_idx;
+  return tu_min16(tu_ff_overflow_count(f->depth, wr_idx, rd_idx), f->depth);
 }
 
 // check if fifo is full
 TU_ATTR_ALWAYS_INLINE static inline bool tu_fifo_full(const tu_fifo_t *f) {
-  return tu_ff_overflow_count(f->depth, f->wr_idx, f->rd_idx) >= f->depth;
+  const uint16_t wr_idx = f->wr_idx;
+  const uint16_t rd_idx = f->rd_idx;
+  return tu_ff_overflow_count(f->depth, wr_idx, rd_idx) >= f->depth;
 }
 
 TU_ATTR_ALWAYS_INLINE static inline uint16_t tu_fifo_remaining(const tu_fifo_t *f) {
-  return tu_ff_remaining_local(f->depth, f->wr_idx, f->rd_idx);
+  const uint16_t wr_idx = f->wr_idx;
+  const uint16_t rd_idx = f->rd_idx;
+  return tu_ff_remaining_local(f->depth, wr_idx, rd_idx);
 }
 
-#if defined(__ICCARM__)
- #pragma diag_default=Pa082
-#endif
-
 #ifdef __cplusplus
 }
 #endif