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Re: Patch AVR: fix call prologue saves for avr6 - commited.
- From: Tristan Gingold <gingold at adacore dot com>
- To: Anatoly Sokolov <aesok at post dot ru>
- Cc: gcc-patches <gcc-patches at gcc dot gnu dot org>, eweddington at cso dot atmel dot com, hutchinsonandy at aim dot com
- Date: Mon, 26 May 2008 10:24:31 +0200
- Subject: Re: Patch AVR: fix call prologue saves for avr6 - commited.
- References: <1697182304.20080526021731@post.ru>
On May 26, 2008, at 12:17 AM, Anatoly Sokolov wrote:
Hi.
If function prologue code placed above low 128K code memory then
linker add
JMP instruction, the code become on 2 words is longer. Hence
"call_prologue"
optimization to become less useful. If for devices with up to 128K
code
memory it is useful when it is necessary to store 6 regs in a
stack, that for
devices with more memory, 6 regs when function prologue code placed
in low
128K and 8 regs when function prologue code placed in high 128K.
Location of
code will be known in link time, therefore when choosing of this
optimization
should be use average value - 7.
Yes, it makes sense.
Thanks.
Tristan.