Index: lib/libc/arch/aarch64/gen/swapcontext.S
===================================================================
RCS file: /cvsroot/src/lib/libc/arch/aarch64/gen/swapcontext.S,v
retrieving revision 1.1
diff -u -p -r1.1 swapcontext.S
--- lib/libc/arch/aarch64/gen/swapcontext.S	10 Aug 2014 05:47:36 -0000	1.1
+++ lib/libc/arch/aarch64/gen/swapcontext.S	21 Nov 2018 20:01:21 -0000
@@ -40,14 +40,14 @@
 
 ENTRY(swapcontext)
 	sub	sp, sp, #32		/* allocate stack frame */
-	stp	x29, x30, [sp, #16]	/* save FP & RA */
+	stp	x29, x30, [sp, #16]	/* save FP & LR */
 	add	x29, sp, #16		/* new FP */
-	stp	x0, x1, [sp, #0]	/* save oucp & ucp */
+	stp	x0, x1, [sp, #0]	/* save oucp (x0) & ucp (x1) */
 
 	bl	_C_LABEL(_getcontext)	/* getcontext(oucp) */
-	mov	x3, x0			/* save return value */
+	mov	x19, x0			/* save return value */
 
-	ldp	x2, x0, [sp, #0]	/* restore oucp & ucp */
+	ldp	x2, x0, [sp, #0]	/* load oucp (x2) & ucp (x1) */
 	ldp	x29, x30, [sp, #16]	/* restore FP & RA */
 	add	sp, sp, #32		/* free stack frame */
 
@@ -58,7 +58,7 @@ ENTRY(swapcontext)
 	str	x4, [x2, #_UC_REGS_SP]	/* Adjust saved SP. */
 	str	x30, [x2, #_UC_REGS_PC]	/* Adjust saved LR. */
 
-	cbz	x3, _C_LABEL(setcontext)/* setcontext if getcontext succeeded */
-	mov	x0, x3			/* restore getcontext return value */
+	cbz	x19, _C_LABEL(setcontext)/* setcontext if getcontext succeeded */
+	mov	x0, x19			/* restore getcontext return value */
 	ret				/* return on error from getcontext */
 END(swapcontext)