From 1432935f0327aaaf4cda72b0f082910a4435b02c Mon Sep 17 00:00:00 2001
From: FeralChild64 <you@example.com>
Date: Sun, 12 Jul 2020 12:13:04 +0200
Subject: [PATCH] added some Mega65 optimizations in BASIC

---
 src/basic/engine/fetch_character.s            |  6 +++
 .../engine/fetch_character_m65_46K_50K.s      | 42 +++++++++++++++++++
 .../engine/fetch_character_skip_spaces.s      |  7 ++++
 .../fetch_character_skip_spaces_m65_46K_50K.s | 41 ++++++++++++++++++
 ...oke_46k_50k.s => under_rom_peek_46k_50k.s} |  0
 5 files changed, 96 insertions(+)
 create mode 100644 src/basic/engine/fetch_character_m65_46K_50K.s
 create mode 100644 src/basic/engine/fetch_character_skip_spaces_m65_46K_50K.s
 rename src/basic/memory/{under_rom_peek_poke_46k_50k.s => under_rom_peek_46k_50k.s} (100%)

diff --git a/src/basic/engine/fetch_character.s b/src/basic/engine/fetch_character.s
index 68397cc7..8c1dcc99 100644
--- a/src/basic/engine/fetch_character.s
+++ b/src/basic/engine/fetch_character.s
@@ -7,6 +7,9 @@
 //
 
 
+// For these configurations we have optimized version in another file
+#if !(ROM_LAYOUT_M65 && (CONFIG_MEMORY_MODEL_46K || CONFIG_MEMORY_MODEL_50K))
+
 fetch_character:
 
 	ldy #0
@@ -46,3 +49,6 @@ consume_character:
 #endif
 
 	rts
+
+
+#endif
diff --git a/src/basic/engine/fetch_character_m65_46K_50K.s b/src/basic/engine/fetch_character_m65_46K_50K.s
new file mode 100644
index 00000000..84363222
--- /dev/null
+++ b/src/basic/engine/fetch_character_m65_46K_50K.s
@@ -0,0 +1,42 @@
+// #LAYOUT# M65 BASIC_0 #TAKE-HIGH
+// #LAYOUT# *   *       #IGNORE
+
+//
+// Fetches a single character - optimized version
+//
+
+
+#if CONFIG_MEMORY_MODEL_46K || CONFIG_MEMORY_MODEL_50K
+
+
+fetch_character:
+
+	ldy #0
+
+	// Unmap BASIC lower ROM
+
+	lda #$26
+	sta CPU_R6510
+
+	// Retrieve value from under ROMs
+
+	lda (TXTPTR), y
+
+	// Restore memory mapping
+
+	pha
+	lda #$27
+	sta CPU_R6510
+	pla
+
+	// FALLTROUGH
+	
+consume_character:
+
+	// Advance basic text pointer
+
+	inw TXTPTR
+	rts
+
+
+#endif
diff --git a/src/basic/engine/fetch_character_skip_spaces.s b/src/basic/engine/fetch_character_skip_spaces.s
index c17eeab7..e67ffc82 100644
--- a/src/basic/engine/fetch_character_skip_spaces.s
+++ b/src/basic/engine/fetch_character_skip_spaces.s
@@ -6,6 +6,10 @@
 // Fetches a single character, but skips spaces
 //
 
+
+// For these configurations we have optimized version in another file
+#if !(ROM_LAYOUT_M65 && (CONFIG_MEMORY_MODEL_46K || CONFIG_MEMORY_MODEL_50K))
+
 fetch_character_skip_spaces:
 
 	jsr fetch_character
@@ -13,3 +17,6 @@ fetch_character_skip_spaces:
 	beq fetch_character_skip_spaces
 
 	rts
+
+
+#endif
diff --git a/src/basic/engine/fetch_character_skip_spaces_m65_46K_50K.s b/src/basic/engine/fetch_character_skip_spaces_m65_46K_50K.s
new file mode 100644
index 00000000..9970a5ef
--- /dev/null
+++ b/src/basic/engine/fetch_character_skip_spaces_m65_46K_50K.s
@@ -0,0 +1,41 @@
+// #LAYOUT# M65 BASIC_0 #TAKE-HIGH
+// #LAYOUT# *   *       #IGNORE
+
+//
+// Fetches a single character, but skips spaces - optimized version
+//
+
+
+#if CONFIG_MEMORY_MODEL_46K || CONFIG_MEMORY_MODEL_50K
+
+
+fetch_character_skip_spaces:
+
+	ldy #0
+
+	// Unmap BASIC lower ROM
+
+	lda #$26
+	sta CPU_R6510
+
+	// Retrieve value from under ROMs, advance text pointer
+!:
+	lda (TXTPTR), y
+	inw TXTPTR
+
+	// Skip space characters
+
+	cmp #$20
+	beq !-
+
+	// Restore memory mapping
+
+	pha
+	lda #$27
+	sta CPU_R6510
+	pla
+
+	rts
+
+
+#endif
diff --git a/src/basic/memory/under_rom_peek_poke_46k_50k.s b/src/basic/memory/under_rom_peek_46k_50k.s
similarity index 100%
rename from src/basic/memory/under_rom_peek_poke_46k_50k.s
rename to src/basic/memory/under_rom_peek_46k_50k.s