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[AVR] Fix private label prefix
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Authored by aykevl on Feb 25 2020, 8:34 AM.

Details

Summary

This is a small pet peeve from me. This change makes sure the AVR backend uses the correct private label prefix (.L) so that private labels are hidden in avr-objdump.

Example code:

define i8 @foo(i1 %cond) {    
  br i1 %cond, label %then, label %else    
then:    
  ret i8 3    
else:    
  ret i8 5    
}

When compiling this:

llc -march=avr -filetype=obj -o test.o test.ll

and then dumping it:

avr-objdump -d test.o

You would previously get an ugly temporary label:

00000000 <foo>:    
   0:        81 70       andi       r24, 0x01    ; 1    
   2:        80 30       cpi        r24, 0x00    ; 0    
   4:        f9 f3       breq       .-2          ; 0x4 <foo+0x4>    
   6:        83 e0       ldi        r24, 0x03    ; 3    
   8:        08 95       ret    

0000000a <LBB0_2>:    
   a:        85 e0       ldi        r24, 0x05    ; 5    
   c:        08 95       ret

This patch fixes that, the output is now:

00000000 <foo>:    
   0:        81 70       andi       r24, 0x01    ; 1    
   2:        80 30       cpi        r24, 0x00    ; 0    
   4:        01 f0       breq       .+0          ; 0x6 <foo+0x6>    
   6:        83 e0       ldi        r24, 0x03    ; 3    
   8:        08 95       ret    
   a:        85 e0       ldi        r24, 0x05    ; 5    
   c:        08 95       ret

Note that as you can see the breq operand is different. However it is still the same after linking:

4:        11 f0       breq       .+4

Diff Detail

Event Timeline

aykevl created this revision.Feb 25 2020, 8:34 AM
dylanmckay accepted this revision.Feb 25 2020, 9:11 PM

Consistency, nice.

This revision is now accepted and ready to land.Feb 25 2020, 9:11 PM
This revision was automatically updated to reflect the committed changes.