1 files changed, 19 insertions, 15 deletions
diff --git a/zap/source/amd64/mem/strcp.S b/zap/source/amd64/mem/strcp.S
index eb5c276..820ed96 100644
--- a/zap/source/amd64/mem/strcp.S
+++ b/zap/source/amd64/mem/strcp.S
@@ -5,35 +5,39 @@
 .globl zap_strcp
 
 zap_strcp:
-	# rax: Address of the current input character.
-	# rdi: Address of the first input character.
-	# rsi: Address of the current output character.
-	# rdx: Current character.
+# Address of the current input character:
+#define iaddr %rax
+# Address of the first input character:
+#define start %rdi
+# Address of the current output character:
+#define oaddr %rsi
+# Current character:
+#define chr   %dl
 
-	movq %rdi,%rax
+	movq start,iaddr
 
 	# Iterate over the strings:
 .loop:
 
 	# Copy character:
-	movb (%rax),%dl # Move it into a register...
-	movb %dl,(%rsi) # ... and then back into memory.
+	movb (iaddr),chr # chr = *iaddr
+	movb chr,(oaddr) # *oaddr = chr
 
 	# Check if we have reached the null-terminator:
-	testb %dl,%dl
-	jz .done
+	testb chr,chr # if (chr == 0x0)
+	jz .done      # goto done
 
 	# Continue to the next character:
 
-	incq %rax
-	incq %rsi
-	jmp .loop
+	incq iaddr # ++iaddr
+	incq oaddr # ++oaddr
+	jmp .loop  # goto loop
 
 	# Finish:
 .done:
 
 	# Get the length of the (input) string:
-	subq %rdi,%rax
-	decq %rax # We do not count the null-terminator in the string length.
+	subq start,iaddr # iaddr -= start
+	decq iaddr       # --iaddr        // We do not count the null-terminator in the string length.
 
-	ret
+	ret # return iaddr