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[avr-gcc-list] gcc prolog incorrect?

From: HutchinsonAndy
Subject: [avr-gcc-list] gcc prolog incorrect?
Date: Sun, 06 Mar 2005 21:12:34 -0500

Is it possible that gcc prolog is incorrect?

  69 000a 0FB6              in __tmp_reg__,__SREG__
  70 000c F894              cli
  71 000e DEBF              out __SP_H__,r29
  72 0010 0FBE              out __SREG__,__tmp_reg__
  73 0012 CDBF              out __SP_L__,r28

This is the code used to adjust the stack pointer for a regular function with 
interrupts active. Basically it turns of interupts so it can chnage both bytes 
of SP without a problem.

But saved BEFORE interrupts are disabled. Doesn't that mean that if interrupts 
were disabled during ISR, a function could re-enabled them when SREG is 

Andy Hutchinson

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