Opened 8 years ago

Closed 8 years ago

#3170 closed bug (fixed)

-fregs-graph: GraphOps.coalesceNodes: can't coalesce the same node.

Reported by: igloo Owned by: benl
Priority: high Milestone: 6.12.1
Component: Compiler Version: 6.10.2
Keywords: Cc:
Operating System: Unknown/Multiple Architecture: Unknown/Multiple
Type of failure: None/Unknown Test Case:
Blocked By: Blocking:
Related Tickets: Differential Rev(s):
Wiki Page:


If -fregs-graph is used then the build fails when compiling PrimOps.cmm:

$ /home/ian/ghc/darcs/ghc/ghc/stage1-inplace/ghc  -Werror -H64m -O0 -fasm -optc-O2 -I../includes -I. -Iparallel -Ism -Ieventlog -DCOMPILING_RTS -package-name rts -static  -I../gmp/gmpbuild -I../libffi/build/include -I. -dcmm-lint     -c PrimOps.cmm -o PrimOps.o -fregs-graph
ghc: panic! (the 'impossible' happened)
  (GHC version 6.11.20090409 for x86_64-unknown-linux):
        GraphOps.coalesceNodes: can't coalesce the same node.

Please report this as a GHC bug:

This blocks #2790.

Change History (2)

comment:1 Changed 8 years ago by benl

Owner: set to benl
Status: newassigned

comment:2 Changed 8 years ago by benl

Resolution: fixed
Status: assignedclosed

Sat Apr 18 18:22:53 EST 2009 Ben.Lippmeier@…

  • Fix #3170: Allow coalescing of the same node during register allocation. The x86 code generator sometimes generates nop moves like movl %vI_a %vI_a, but we'll just ignore them for coalescing purposes instead of emitting an error. It shouldn't hurt anything.
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