1 files changed, 29 insertions, 25 deletions
diff --git a/zap/source/amd64/mem/foreach.S b/zap/source/amd64/mem/foreach.S
index f19bcfa..6766933 100644
--- a/zap/source/amd64/mem/foreach.S
+++ b/zap/source/amd64/mem/foreach.S
@@ -5,51 +5,55 @@
 .globl zap_foreach
 
 zap_foreach:
-	# rbx: Address of the current element.
-	# r12: Address of the element after the last input element.
-	# r13: Size of each input element.
-	# r14: Address of the function.
+# Address of the current element:
+#define addr     %rbx
+# Address of the element after the last input element:
+#define afterbuf %r12
+# Size of each input element:
+#define sz       %r13
+# Address of the function:
+#define fn       %r14
 
 	# We're gonna use callee-saved registers for storing values so they don't get overwritten with each function call.
 
 	# Push the callee-saved registers:
-	pushq %rbx
-	pushq %r12
-	pushq %r13
-	pushq %r14
+	pushq addr
+	pushq afterbuf
+	pushq sz
+	pushq fn
 
 	# Move registers into place:
-	movq %rdi,%rbx
-	movq %rsi,%r13
-	movq %rcx,%r14
+	movq %rdi,addr
+	movq %rsi,sz
+	movq %rcx,fn
 
 	# Get the one-past-the-end address:
-	movq %rdx,%r12
-	imulq %r13,%r12 # Calculate the array size in bytes (sz * num). We're using signed multiply because the equivalent using the unsigned instruction would use more instructions.
-	addq %rbx,%r12
+	movq %rdx,afterbuf
+	imulq sz,afterbuf  # afterbuf *= sz   // Calculate the array size in bytes (sz * num). We're using signed multiply because the equivalent using the unsigned instruction would use more instructions.
+	addq addr,afterbuf # afterbuf += addr
 
 	# Iterate through the array:
 .loop:
 
 	# Check if we have reached the one-past-the-end address:
-	cmpq %rbx,%r12
-	je .done
+	cmpq addr,afterbuf # if (addr == afterbuf)
+	je .done           # goto done
 
 	# Call the provided function:
-	movq %rbx,%rdi # Provide the current address to the function.
-	call *%r14 # We don't need to save any registers for this as we only use callee-saved registers.
+	movq addr,%rdi #          // Provide the current address to the function.
+	call *fn       # fn(addr) // We don't need to save any registers for this as we only use callee-saved registers.
 
 	# Continue to the next element:
-	addq %r13,%rbx
-	jmp .loop
+	addq sz,addr # addr += sz
+	jmp .loop    # goto loop
 
 	# Finish:
 .done:
 	
 	# Restore the callee-saved registers:
-	popq %r14
-	popq %r13
-	popq %r12
-	popq %rbx
+	popq fn
+	popq sz
+	popq afterbuf
+	popq addr
 
-	ret
+	ret # return