Rename safe_add to clamp_add

Makefile

 PRG            = crowbx
-OBJ            = crowbx.o midi.o dac.o uart.o gate.o poly.o mono.o list.o vibrato.o poly2.o safe_add.o pitch.o pitch_env.o vibrato_rate.o mono2.o voice.o
+OBJ            = crowbx.o midi.o dac.o uart.o gate.o poly.o mono.o list.o vibrato.o poly2.o clamp_add.o pitch.o pitch_env.o vibrato_rate.o mono2.o voice.o
 MCU_TARGET = atmega328p
 
 OPTIMIZE       = -O3

safe_add.c → clamp_add.c

-#include "safe_add.h"
+#include "clamp_add.h"
 
-uint16_t safe_add(uint16_t x, int16_t delta) {
+uint16_t clamp_add(uint16_t x, int16_t delta) {
 	if (delta < 0) {
 		uint16_t sub = -delta;
 		if (x < sub) {

clamp_add.h

+#ifndef CLAMP_ADD_H
+#define CLAMP_ADD_H
+
+#include <stdint.h>
+
+uint16_t clamp_add(uint16_t x, int16_t delta);
+
+#endif

dac.c

 #include "dac.h"
-#include "safe_add.h"
+#include "clamp_add.h"
 #include "voice.h"
 #include <avr/io.h>
 #include <util/delay.h>
@@ -84,7 +84,7 @@ uint16_t dac_note_pitch(uint8_t v, uint8_t note) {
 		return 0;
 	}
 
-	return safe_add(
+	return clamp_add(
 	    d->offset + octave * d->scale,
 	    dac_semitone_offset((note - MIDI_LOWEST) % NUM_SEMITONES));
 }

pitch.c

 #include "pitch.h"
 #include "dac.h"
 #include "pitch_env.h"
-#include "safe_add.h"
+#include "clamp_add.h"
 #include "vibrato.h"
 #include "voice.h"
 
@@ -19,7 +19,7 @@ void pitch_set_note(uint8_t voice, uint8_t note, int16_t detune) {
 		return;
 	}
 
-	base_pitch[voice] = safe_add(dac_note_pitch(voice, note), detune);
+	base_pitch[voice] = clamp_add(dac_note_pitch(voice, note), detune);
 }
 
 void pitch_set_bend(uint16_t bend) {
@@ -32,10 +32,10 @@ void pitch_update_clock(uint8_t delta) {
 	pitch_env_update_clock(delta);
 
 	for_each_voice (v) {
-		uint16_t data = safe_add(base_pitch[v], vibrato_detune());
-		data = safe_add(data,
+		uint16_t data = clamp_add(base_pitch[v], vibrato_detune());
+		data = clamp_add(data,
 				pitch_env_delta(v) * (float)dac_pitch_delta(5));
-		data = safe_add(data, bend_data);
+		data = clamp_add(data, bend_data);
 		dac_send(dac_command_set(v), data);
 	}
 }

safe_add.h

-#ifndef SAFE_ADD_H
-#define SAFE_ADD_H
-
-#include <stdint.h>
-
-uint16_t safe_add(uint16_t x, int16_t delta);
-
-#endif