* RFA: RL78: Always select register bank 0 at the start of an ISR
@ 2013-01-03 12:49 Nick Clifton
2013-01-07 19:54 ` DJ Delorie
0 siblings, 1 reply; 2+ messages in thread
From: Nick Clifton @ 2013-01-03 12:49 UTC (permalink / raw)
To: dj; +Cc: gcc-patches
Hi DJ,
Since interrupts can happen at any time, it is possible for a ISR to
be called when register bank 0 is not the currently selected bank.
Hence the prologue for an interrupt handler should always select bank
0 before saving any registers. The patch below makes sure that this
happens.
No regressions with a rl78-elf toolchain.
OK to apply ?
Cheers
Nick
gcc/ChangeLog
2013-01-03 Nick Clifton <nickc@redhat.com>
* config/rl78/rl78.c (rl78_expand_prologue): Always select
register bank 0 at the start of an interrupt handler.
Index: gcc/config/rl78/rl78.c
===================================================================
--- gcc/config/rl78/rl78.c (revision 194833)
+++ gcc/config/rl78/rl78.c (working copy)
@@ -839,6 +839,9 @@
if (flag_stack_usage_info)
current_function_static_stack_size = cfun->machine->framesize;
+ if (is_interrupt_func (cfun->decl))
+ emit_insn (gen_sel_rb (GEN_INT (0)));
+
for (i = 0; i < 16; i++)
if (cfun->machine->need_to_push [i])
{
^ permalink raw reply [flat|nested] 2+ messages in thread
* Re: RFA: RL78: Always select register bank 0 at the start of an ISR
2013-01-03 12:49 RFA: RL78: Always select register bank 0 at the start of an ISR Nick Clifton
@ 2013-01-07 19:54 ` DJ Delorie
0 siblings, 0 replies; 2+ messages in thread
From: DJ Delorie @ 2013-01-07 19:54 UTC (permalink / raw)
To: Nick Clifton; +Cc: gcc-patches
I think that's right, since the ISR return restores the flag register,
which has the bank select bits in it.
^ permalink raw reply [flat|nested] 2+ messages in thread
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2013-01-03 12:49 RFA: RL78: Always select register bank 0 at the start of an ISR Nick Clifton
2013-01-07 19:54 ` DJ Delorie
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