Set Carry Flag If Returned Value Is Between [-1, -4095]

Based off of how we handle the carry flag for x86.
darlinghq · Feb 12, 2024 · 59096eb · 59096eb
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commit 59096eb
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diff --git a/gen/bsdsyscalls/SYS.h b/gen/bsdsyscalls/SYS.h
@@ -476,11 +476,14 @@ pseudo:									;\
  */
 
 #ifdef DARLING
+// In addition to changing the macro to use __darling_handle_svc instead of the
+// syscall (svc) instruction, We are also setting the carry flag as well.
 #define DO_SYSCALL(num, cerror)                 \
 	mov   x16, #(num)                     %%\
 	PUSH_FRAME                            %%\
 	bl    __darling_handle_svc            %%\
 	POP_FRAME                             %%\
+	cmn x0, #4095                         %%\
 	b.cc  2f                              %%\
 	ARM64_STACK_PROLOG                    %%\
 	PUSH_FRAME                            %%\

diff --git a/libsyscall/custom/SYS.h b/libsyscall/custom/SYS.h
@@ -476,11 +476,14 @@ pseudo:									;\
  */
 
 #ifdef DARLING
+// In addition to changing the macro to use __darling_handle_svc instead of the
+// syscall (svc) instruction, We are also setting the carry flag as well.
 #define DO_SYSCALL(num, cerror)                 \
 	mov   x16, #(num)                     %%\
 	PUSH_FRAME                            %%\
 	bl    __darling_handle_svc            %%\
 	POP_FRAME                             %%\
+	cmn x0, #4095                         %%\
 	b.cc  2f                              %%\
 	ARM64_STACK_PROLOG                    %%\
 	PUSH_FRAME                            %%\