meta-xilinx/meta-xilinx-bsp/recipes-microblaze/gcc/gcc-7/0015-MicroBlaze-fixed-missing-save-of-r18-in-fast_interru.patch

From 79ea36649467aea6045a49c7d016f8f9245efb8c Mon Sep 17 00:00:00 2001
From: Mahesh Bodapati <mbodapat@xilinx.com>
Date: Sat, 26 Aug 2017 19:21:29 -0700
Subject: [PATCH] MicroBlaze fixed missing save of r18 in fast_interrupt

Fixed missing save of r18 in fast_interrupt. Register 18 is used as a
clobber register, and must be stored when entering a fast_interrupt.
Before this fix, register 18 was only saved if it was used directly in
the interrupt function.

However, if the fast_interrupt function called a function that used
r18, the register would not be saved, and thus be mangled
upon returning from the interrupt.

Changelog

2014-02-27  Klaus Petersen <klauspetersen@gmail.com>

 * gcc/config/microblaze/microblaze.c: Check for fast_interrupt in
   microblaze_must_save_register.

Signed-off-by: Klaus Petersen <klauspetersen@gmail.com>
Signed-off-by: David Holsgrove <david.holsgrove@xilinx.com>
Signed-off-by: Mahesh Bodapati <mbodapat@xilinx.com>
Signed-off-by: Manjukumar Matha <manjukumar.harthikote-matha@xilinx.com>
Upstream-Status: Pending
---
 gcc/config/microblaze/microblaze.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/gcc/config/microblaze/microblaze.c b/gcc/config/microblaze/microblaze.c
index 15080db539..558796cad9 100644
--- a/gcc/config/microblaze/microblaze.c
+++ b/gcc/config/microblaze/microblaze.c
@@ -1943,7 +1943,7 @@ microblaze_must_save_register (int regno)
     {
       if (df_regs_ever_live_p (regno) 
 	  || regno == MB_ABI_MSR_SAVE_REG
-	  || (interrupt_handler
+	  || ((interrupt_handler || fast_interrupt)
               && (regno == MB_ABI_ASM_TEMP_REGNUM
 	          || regno == MB_ABI_EXCEPTION_RETURN_ADDR_REGNUM)))
 	return 1;
-- 
2.14.2