Crash in Live Variable Analysis

[pwo]

Bugzilla Link	8716
Resolution	WORKSFORME
Resolved on	Dec 02, 2010 00:24
Version	trunk
OS	FreeBSD
Attachments	bugpoint-reduced-simplified.bc, valgrind.log
CC	@atrick,@stoklund

Extended Description

$ llc bugpoint-reduced-simplified.bcStack dump:
0. Program arguments: /data/buildslave/freebsd-clang-amd64/obj/obj-llvm.2/Release+Asserts/bin/llc bugpoint-reduced-simplified.bc

1. Running pass 'Function Pass Manager' on module 'bugpoint-reduced-simplified.bc'.
2. Running pass 'Live Variable Analysis' on function '@tgamma'
   Segmentation fault (core dumped)

Reduced from FreeBSD lib/msun/bsdsrc/b_tgamma.c.

[pwo]

This problem was recently introduced, between r120381 and r120528.

Only seen on amd64.

[stoklund]

This no longer reproduces on TOT. Please verify.

(I was able to reproduce with r120526, but not r120580)

[stoklund]

llc -verify-machineinstrs says:

*** Bad machine code: PHI operand is not live-out from predecessor ***

• function: tgamma
• basic block: if.then34.i 0x101049a18 (BB#8)
• instruction: %reg16385 = PHI %reg16393, <BB#6>, %reg16384, <BB#7>; FR64:%reg16385,16393,16384
• operand 3: %reg16384
  LLVM ERROR: Found 1 machine code errors.

I think Evan had a similar problem yesterday and reverted something.

[pwo]

This no longer reproduces on TOT. Please verify.

(I was able to reproduce with r120526, but not r120580)

Yep, works fine now. Sorry for the hassle.