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]>

Author: dpgeorge

py/nlraarch64.c

@@ -75,7 +75,7 @@ NORETURN void nlr_jump(void *val) {
         "ret                     \n"
         :
         : "r" (top)
-        :
+        : "memory"
         );
 
     MP_UNREACHABLE

py/nlrmips.c

@@ -78,7 +78,7 @@ NORETURN void nlr_jump(void *val) {
         "nop            \n"
         :
         : "r" (top)
-        :
+        : "memory"
         );
     MP_UNREACHABLE
 }

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;

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

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

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

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