From a03c5ac700c34794c332aa2c558979a1368d2851 Mon Sep 17 00:00:00 2001
From: Virgil Dupras <hsoft@hardcoded.net>
Date: Fri, 22 Nov 2019 17:16:51 -0500
Subject: [PATCH] lib/expr: add bitwise operators

---
 apps/README.md                 |  6 +++++-
 apps/lib/expr.asm              | 43 +++++++++++++++++++++++++++++++++++++++++-
 tools/tests/unit/test_expr.asm | 15 +++++++++++++++
 3 files changed, 62 insertions(+), 2 deletions(-)

diff --git a/apps/README.md b/apps/README.md
index 6265bd6..3623acc 100644
--- a/apps/README.md
+++ b/apps/README.md
@@ -90,7 +90,11 @@ this way, it's going to mess with the parser.
 ### Expressions
 
 An expression is a bunch of literals or symbols assembled by operators.
-Supported operators are `+`, `-`, `*`, `/` and `%` (modulo). No parenthesis yet.
+Supported operators are `+`, `-`, `*`, `/`, `%` (modulo), `&` (bitwise and),
+`|` (bitwise or) and `^` (bitwise xor). Bitwise operator always operate on
+the whole 16-bits.
+
+There is no parenthesis support yet.
 
 Symbols have a different meaning depending on the application. In zasm, it's
 labels and constants. In basic, it's variables.
diff --git a/apps/lib/expr.asm b/apps/lib/expr.asm
index 1816e3f..982f3fe 100644
--- a/apps/lib/expr.asm
+++ b/apps/lib/expr.asm
@@ -117,6 +117,12 @@ exprTbl:
 	.dw	.div
 	.db	'%'
 	.dw	.mod
+	.db	'&'
+	.dw	.and
+	.db	0x7c		; '|'
+	.dw	.or
+	.db	'^'
+	.dw	.xor
 	.db	0		; end of table
 
 .plus:
@@ -155,5 +161,40 @@ exprTbl:
 
 .mod:
 	call	.div
-	push	hl \ pop	ix
+	push	hl \ pop ix
+	ret
+
+.and:
+	push	ix \ pop hl
+	ld	a, h
+	and	d
+	ld	h, a
+	ld	a, l
+	and	e
+	ld	l, a
+	push	hl \ pop ix
+	cp	a		; ensure Z
+	ret
+.or:
+	push	ix \ pop hl
+	ld	a, h
+	or	d
+	ld	h, a
+	ld	a, l
+	or	e
+	ld	l, a
+	push	hl \ pop ix
+	cp	a		; ensure Z
+	ret
+
+.xor:
+	push	ix \ pop hl
+	ld	a, h
+	xor	d
+	ld	h, a
+	ld	a, l
+	xor	e
+	ld	l, a
+	push	hl \ pop ix
+	cp	a		; ensure Z
 	ret
diff --git a/tools/tests/unit/test_expr.asm b/tools/tests/unit/test_expr.asm
index 1c11d75..f8c3342 100644
--- a/tools/tests/unit/test_expr.asm
+++ b/tools/tests/unit/test_expr.asm
@@ -139,6 +139,12 @@ testParseExpr:
 	call	.testEQ
 	ld	iy, .t2
 	call	.testEQ
+	ld	iy, .t3
+	call	.testEQ
+	ld	iy, .t4
+	call	.testEQ
+	ld	iy, .t5
+	call	.testEQ
 	ret
 
 .testEQ:
@@ -161,6 +167,15 @@ testParseExpr:
 .t2:
 	.dw	1
 	.db	"7%3", 0
+.t3:
+	.dw	0x0907
+	.db	"0x99f7&0x0f0f", 0
+.t4:
+	.dw	0x9fff
+	.db	"0x99f7|0x0f0f", 0
+.t5:
+	.dw	0x96f8
+	.db	"0x99f7^0x0f0f", 0
 
 nexttest:
 	ld	a, (testNum)