py/nlr: Add "memory" to asm clobbers list in nlr_jump.

Newer versions of gcc (14 and up) have more sophisticated dead-code detection, and the asm clobbers list needs to contain "memory" to inform the compiler that the asm code actually does something. Tested that adding this "memory" line does not change the generated code on ARM Thumb2, x86-64 and Xtensa targets (using gcc 13.2). Fixes issue micropython#14115. Signed-off-by: Damien George <[email protected]>
picoscratch · Mar 25, 2024 · 35f3f0a · 35f3f0a
1 parent 35b2edf
commit 35f3f0a
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Showing 7 changed files with 8 additions and 8 deletions.
diff --git a/py/nlraarch64.c b/py/nlraarch64.c
@@ -75,7 +75,7 @@ NORETURN void nlr_jump(void *val) {
         "ret                     \n"
         :
         : "r" (top)
-        :
+        : "memory"
         );
 
     MP_UNREACHABLE

diff --git a/py/nlrmips.c b/py/nlrmips.c
@@ -78,7 +78,7 @@ NORETURN void nlr_jump(void *val) {
         "nop            \n"
         :
         : "r" (top)
-        :
+        : "memory"
         );
     MP_UNREACHABLE
 }

diff --git a/py/nlrpowerpc.c b/py/nlrpowerpc.c
@@ -114,7 +114,7 @@ NORETURN void nlr_jump(void *val) {
         "blr ;"
         :
         : "r" (&top->regs)
-        :
+        : "memory"
         );
 
     MP_UNREACHABLE;
@@ -203,7 +203,7 @@ NORETURN void nlr_jump(void *val) {
         "blr ;"
         :
         : "r" (&top->regs)
-        :
+        : "memory"
         );
 
     MP_UNREACHABLE;

diff --git a/py/nlrthumb.c b/py/nlrthumb.c
@@ -132,7 +132,7 @@ NORETURN void nlr_jump(void *val) {
         "bx     lr                  \n" // return
         :                           // output operands
         : "r" (top)                 // input operands
-        :                           // clobbered registers
+        : "memory"                  // clobbered registers
         );
 
     MP_UNREACHABLE

diff --git a/py/nlrx64.c b/py/nlrx64.c
@@ -123,7 +123,7 @@ NORETURN void nlr_jump(void *val) {
         "ret                        \n" // return
         :                           // output operands
         : "r" (top)                 // input operands
-        :                           // clobbered registers
+        : "memory"                  // clobbered registers
         );
 
     MP_UNREACHABLE

diff --git a/py/nlrx86.c b/py/nlrx86.c
@@ -95,7 +95,7 @@ NORETURN void nlr_jump(void *val) {
         "ret                        \n" // return
         :                           // output operands
         : "r" (top)                 // input operands
-        :                           // clobbered registers
+        : "memory"                  // clobbered registers
         );
 
     MP_UNREACHABLE

diff --git a/py/nlrxtensa.c b/py/nlrxtensa.c
@@ -74,7 +74,7 @@ NORETURN void nlr_jump(void *val) {
         "ret.n                      \n" // return
         :                           // output operands
         : "r" (top)                 // input operands
-        :                           // clobbered registers
+        : "memory"                  // clobbered registers
         );
 
     MP_UNREACHABLE