From: Jozef Lawrynowicz <jozef.l@mittosystems.com>
Date: Tue, 21 Jul 2020 16:24:03 +0000 (+0100)
Subject: MSP430: Define NO_FUNCTION_CSE
X-Git-Url: https://git.libre-soc.org/?a=commitdiff_plain;h=111afded7fdf46ce14972aa8a72c26c9a180ab70;p=gcc.git

MSP430: Define NO_FUNCTION_CSE

Calling a constant function address costs the same number of clock
cycles as calling an address stored in a register. However, in terms of
instruction length, calling a constant address is more expensive.

Set NO_FUNCTION_CSE to true, only when optimizing for speed.

gcc/ChangeLog:

	* config/msp430/msp430.h (NO_FUNCTION_CSE): Set to true at -O2 and
	above.
---

diff --git a/gcc/config/msp430/msp430.h b/gcc/config/msp430/msp430.h
index f198981ad9e..e97e833a10c 100644
--- a/gcc/config/msp430/msp430.h
+++ b/gcc/config/msp430/msp430.h
@@ -257,6 +257,11 @@ extern const char *msp430_get_linker_devices_include_path (int, const char **);
   msp430_return_addr_rtx (COUNT)
 
 #define SLOW_BYTE_ACCESS		0
+
+/* Calling a constant function address costs the same number of clock
+   cycles as calling an address stored in a register. However, in terms of
+   instruction length, calling a constant address is more expensive.  */
+#define NO_FUNCTION_CSE (optimize >= 2 && !optimize_size)
 
 
 /* Register Usage */