From bbe3e21a54897d8ab3bec3fbbf02e908363dd28b Mon Sep 17 00:00:00 2001
From: zerico <71151164+ZERICO2005@users.noreply.github.com>
Date: Tue, 21 Apr 2026 12:30:14 -0600
Subject: [PATCH] added CRT absolute value functions

---
 src/crt/babs.src   | 13 +++++++++++++
 src/crt/i48abs.src | 18 ++++++++++++++++++
 src/crt/iabs.src   | 16 ++++++++++++++++
 src/crt/labs.src   | 14 ++++++++++++++
 src/crt/llabs.src  | 14 ++++++++++++++
 src/crt/sabs.src   | 14 ++++++++++++++
 6 files changed, 89 insertions(+)
 create mode 100644 src/crt/babs.src
 create mode 100644 src/crt/i48abs.src
 create mode 100644 src/crt/iabs.src
 create mode 100644 src/crt/labs.src
 create mode 100644 src/crt/llabs.src
 create mode 100644 src/crt/sabs.src

diff --git a/src/crt/babs.src b/src/crt/babs.src
new file mode 100644
index 000000000..e7a446e23
--- /dev/null
+++ b/src/crt/babs.src
@@ -0,0 +1,13 @@
+	.assume	adl=1
+
+	.section	.text
+
+	.global	__babs
+	.type	__babs, @function
+
+__babs:
+	; A = abs(A)
+	or	a, a
+	ret	p
+	neg
+	ret
diff --git a/src/crt/i48abs.src b/src/crt/i48abs.src
new file mode 100644
index 000000000..984448c5e
--- /dev/null
+++ b/src/crt/i48abs.src
@@ -0,0 +1,18 @@
+	.assume	adl=1
+
+	.section	.text
+
+	.global	__i48abs
+	.type	__i48abs, @function
+
+__i48abs:
+	; UDE:UHL = abs(UDE:UHL)
+	ex	de, hl
+	add	hl, de
+	or	a, a
+	sbc	hl, de
+	ex	de, hl
+	ret	p
+	jp	__i48neg
+
+	.extern	__i48neg
diff --git a/src/crt/iabs.src b/src/crt/iabs.src
new file mode 100644
index 000000000..02cf2b396
--- /dev/null
+++ b/src/crt/iabs.src
@@ -0,0 +1,16 @@
+	.assume	adl=1
+
+	.section	.text
+
+	.global	__iabs
+	.type	__iabs, @function
+
+__iabs:
+	; UHL = abs(UHL)
+	add	hl, bc
+	or	a, a
+	sbc	hl, bc
+	ret	p
+	jp	__ineg
+
+	.extern	__ineg
diff --git a/src/crt/labs.src b/src/crt/labs.src
new file mode 100644
index 000000000..f4420595d
--- /dev/null
+++ b/src/crt/labs.src
@@ -0,0 +1,14 @@
+	.assume	adl=1
+
+	.section	.text
+
+	.global	__labs
+	.type	__labs, @function
+
+__labs:
+	; E:UHL = abs(E:UHL)
+	bit	7, e
+	ret	z
+	jp	__lneg
+
+	.extern	__lneg
diff --git a/src/crt/llabs.src b/src/crt/llabs.src
new file mode 100644
index 000000000..ac0aaa1f4
--- /dev/null
+++ b/src/crt/llabs.src
@@ -0,0 +1,14 @@
+	.assume	adl=1
+
+	.section	.text
+
+	.global	__llabs
+	.type	__llabs, @function
+
+__llabs:
+	; BC:UDE:UHL = abs(BC:UDE:UHL)
+	bit	7, b
+	ret	z
+	jp	__llneg
+
+	.extern	__llneg
diff --git a/src/crt/sabs.src b/src/crt/sabs.src
new file mode 100644
index 000000000..ad71ba1f3
--- /dev/null
+++ b/src/crt/sabs.src
@@ -0,0 +1,14 @@
+	.assume	adl=1
+
+	.section	.text
+
+	.global	__sabs
+	.type	__sabs, @function
+
+__sabs:
+	; HL = abs(HL)
+	bit	7, h
+	ret	z
+	jp	__sneg
+
+	.extern	__sneg