From 343129a61099f74ab746905a693d7b18ced6b269 Mon Sep 17 00:00:00 2001
From: pommicket <pommicket@gmail.com>
Date: Tue, 11 Jan 2022 18:03:09 -0500
Subject: full multiply

---
 05/main.b     |  5 ++++-
 05/tokenize.b | 10 +++++++---
 05/util.b     | 29 ++++++++++++++++++++++++++++-
 3 files changed, 39 insertions(+), 5 deletions(-)

diff --git a/05/main.b b/05/main.b
index f21438f..b500150 100644
--- a/05/main.b
+++ b/05/main.b
@@ -88,7 +88,6 @@ function main
 	local tokens
 	
 	fill_in_powers_of_10()
-	print_powers_of_10()
 	
 	dat_banned_objmacros = 255
 	dat_banned_fmacros = 255
@@ -142,6 +141,10 @@ function main
 	string a.out
 	byte 0
 
+; NOTE: this language doesn't have proper support for floating-point numbers,
+; but we need to do some float stuff. floats are stored as a 58-bit significand
+; and an exponent. the significand ranges from 0 (inclusive) to 0x400000000000000 (exclusive)
+
 function normalize_float
 	argument p_significand
 	argument p_exponent
diff --git a/05/tokenize.b b/05/tokenize.b
index 3715fc1..1c197a7 100644
--- a/05/tokenize.b
+++ b/05/tokenize.b
@@ -120,6 +120,8 @@ function tokenize
 	local n
 	local p
 	local data
+	local significand
+	local exponent
 	
 	in = pptokens
 	:tokenize_loop
@@ -236,9 +238,6 @@ function tokenize
 			out += 2 ; no info
 			data = c
 			goto token_output
-		:tokenize_float
-			; @TODO
-			byte 0xcc
 		:tokenize_string_literal
 			n = rodata_end_offset - RODATA_OFFSET
 			n += RODATA_ADDR ; address of string
@@ -261,6 +260,11 @@ function tokenize
 			out += 2 ; no info
 			data = n
 			goto token_output
+		:tokenize_float
+			significand = 0
+			exponent = 0
+			; @TODO
+			byte 0xcc
 	:tokenize_loop_end
 	
 	return 0
diff --git a/05/util.b b/05/util.b
index 177c31e..190c736 100644
--- a/05/util.b
+++ b/05/util.b
@@ -1,4 +1,31 @@
-
+; multiply two 64-bit signed numbers to a 128-bit number
+function full_multiply_signed
+	argument a
+	argument b
+	argument p_lower
+	argument p_upper
+	local lower
+	local upper
+	
+	lower = a * b
+	; mov rax, rdx
+	byte 0x48
+	byte 0x89
+	byte 0xd0
+	; mov [rbp-48] (upper), rax
+	byte 0x48
+	byte 0x89
+	byte 0x85
+	byte 0xd0
+	byte 0xff
+	byte 0xff
+	byte 0xff
+	
+	*8p_lower = lower
+	*8p_upper = upper
+	return
+	
+	
 function file_error
 	argument name
 	fputs(2, .str_file_error)
-- 
cgit v1.2.3