prolog/epilog

[sevtov]

>>       I've observed RTL-code for i386, ARM and AVR machine and
>>       I found that i386 and ARM RTL contain the code for
>>       epilog&prolog of a function 
>>       But AVR-RTL-code doesn't. Why???

JW> We have two ways of emitting prologue/epilogue code.  The old way emits 
JW> assembler code directly.  The new way emits RTL code.  The new way is 
JW> preferred, but not all targets have been modified to use it.  The avr is 
JW> a relatively new port though, it should have used the new way from the 
JW> start, so this looks like an oversight when it was written.  Maybe the 
JW> docs on this matter aren't clear.

Thank you for your reply.

You wrote the AVR port should contains epilog/prolog code insight RTL.
But I compared two rtl-code :
- produced by i386 cross-compiler
- produced by AVR cross-compiler

The first had the following notes :

(note 69 68 5 NOTE_INSN_PROLOGUE_END)

(note 52 37 53 NOTE_INSN_EPILOGUE_BEG)

But AVR doesn't.

Thank you for your attention.