[GHC] #12075: Fails to build on powerpcspe because of inline assembly

[GHC]

#12075: Fails to build on powerpcspe because of inline assembly
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           Reporter:  glaubitz  |             Owner:
               Type:  bug       |            Status:  new
           Priority:  normal    |         Milestone:
          Component:  Compiler  |           Version:  8.0.1
           Keywords:            |  Operating System:  Linux
       Architecture:  powerpc   |   Type of failure:  Building GHC failed
          Test Case:            |        Blocked By:
           Blocking:            |   Related Tickets:
Differential Rev(s):            |         Wiki Page:
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 Hello!

 I'm currently bootstrapping GHC on powerpcspe (e500v2) which is a PowerPC
 architecture without an FPU but with signal processing extensions (hence
 SPE).

 When building GHC on this architecture, it detects the host architecture
 as powerpc-linux-gnuspe or short "powerpc" which works most of the time.

 However, GHC contains some inline assembly in rts/StgCRunAsm.s which uses
 FPU instructions not available on e500v2 CPUs resulting in assembler
 error, here with GHC 7.10.3:

 {{{
 "inplace/bin/ghc-stage1" -optc-fno-stack-protector -optc-Wall -optc-Wextra
 -optc-Wstrict-prototypes -optc-Wmissing-prototypes -optc-Wmissing-
 declarations -optc-Winline -optc-Waggregate-return -optc-Wpointer-arith
 -optc-Wmissing-noreturn -optc-Wnested-externs -optc-Wredundant-decls
 -optc-Iincludes -optc-Iincludes/dist -optc-Iincludes/dist-
 derivedconstants/header -optc-Iincludes/dist-ghcconstants/header -optc-
 Irts -optc-Irts/dist/build -optc-DCOMPILING_RTS -optc-
 DUSE_LIBFFI_FOR_ADJUSTORS -optc-fno-strict-aliasing -optc-fno-common
 -optc-Irts/dist/build/autogen -optc-O2 -optc-fomit-frame-pointer -optc-g
 -optc-DRtsWay=\"rts_v\" -optc-w -static  -H32m -O -lffi -optl-pthread
 -lffi -optl-pthread -Iincludes -Iincludes/dist -Iincludes/dist-
 derivedconstants/header -Iincludes/dist-ghcconstants/header -Irts
 -Irts/dist/build -DCOMPILING_RTS -this-package-key rts -dcmm-lint      -i
 -irts -irts/dist/build -irts/dist/build/autogen -Irts/dist/build
 -Irts/dist/build/autogen           -O2    -c rts/StgCRun.c -o
 rts/dist/build/StgCRun.o
 /bin/bash: warning: setlocale: LC_ALL: cannot change locale (en_US.UTF-8)
 /bin/bash: warning: setlocale: LC_ALL: cannot change locale (en_US.UTF-8)
 /tmp/ghcf20d_0/ghc_1.s: Assembler messages:

 /tmp/ghcf20d_0/ghc_1.s:24:0:  Error: unrecognized opcode: `stfd'

 (...)

 /tmp/ghcf20d_0/ghc_1.s:67:0:  Error: unrecognized opcode: `lfd'

 /tmp/ghcf20d_0/ghc_1.s:68:0:  Error: unrecognized opcode: `lfd'

 /tmp/ghcf20d_0/ghc_1.s:69:0:  Error: unrecognized opcode: `lfd'
 rts/ghc.mk:236: recipe for target 'rts/dist/build/StgCRun.o' failed
 make[3]: *** [rts/dist/build/StgCRun.o] Error 1
 Makefile:71: recipe for target 'all' failed
 make[2]: *** [all] Error 2
 make[2]: Leaving directory '/usr/src/ghc-7.10.3'
 dh_auto_build: make -j1 returned exit code 2
 debian/rules:109: recipe for target 'override_dh_auto_build' failed
 make[1]: *** [override_dh_auto_build] Error 2
 make[1]: Leaving directory '/usr/src/ghc-7.10.3'
 debian/rules:47: recipe for target 'binary-arch' failed
 make: *** [binary-arch] Error 2
 (sid2-powerpcspe-sbuild)root at atlantis:/usr/src/ghc-7.10.3#
 }}}

 This can be verified by commenting out the assembly which will make the
 above compile command execute without any problems. Trying to continue
 compiling GHC will still fail with:

 {{{
 "inplace/bin/ghc-stage1" -static  -H32m -O -lffi -optl-pthread -lffi
 -optl-pthread -Iincludes -Iincludes/dist -Iincludes/dist-
 derivedconstants/header -Iincludes/dist-ghcconstants/header -Irts
 -Irts/dist/build -DCOMPILING_RTS -this-package-key rts -dcmm-lint      -i
 -irts -irts/dist/build -irts/dist/build/autogen -Irts/dist/build
 -Irts/dist/build/autogen           -O2    -c rts/HeapStackCheck.cmm -o
 rts/dist/build/HeapStackCheck.o
 /bin/bash: warning: setlocale: LC_ALL: cannot change locale (en_US.UTF-8)
 /bin/bash: warning: setlocale: LC_ALL: cannot change locale (en_US.UTF-8)
 /tmp/ghcca51_0/ghc_3.s: Assembler messages:

 /tmp/ghcca51_0/ghc_3.s:525:0:  Error: unrecognized opcode: `lfs'

 /tmp/ghcca51_0/ghc_3.s:538:0:  Error: unrecognized opcode: `lfd'

 /tmp/ghcca51_0/ghc_3.s:592:0:  Error: unrecognized opcode: `stfs'

 /tmp/ghcca51_0/ghc_3.s:604:0:  Error: unrecognized opcode: `stfd'
 rts/ghc.mk:236: recipe for target 'rts/dist/build/HeapStackCheck.o' failed
 make[3]: *** [rts/dist/build/HeapStackCheck.o] Error 1
 Makefile:71: recipe for target 'all' failed
 make[2]: *** [all] Error 2
 make[2]: Leaving directory '/usr/src/ghc-7.10.3'
 dh_auto_build: make -j1 returned exit code 2
 debian/rules:109: recipe for target 'override_dh_auto_build' failed
 make[1]: *** [override_dh_auto_build] Error 2
 make[1]: Leaving directory '/usr/src/ghc-7.10.3'
 debian/rules:47: recipe for target 'binary-arch' failed
 make: *** [binary-arch] Error 2
 (sid2-powerpcspe-sbuild)root at atlantis:/usr/src/ghc-7.10.3#
 }}}

 So, there is obviously more assembly code that needs to be disabled on
 powerpcspe.

 For that, I suggest testing whether the compiler sets __NO_FPRS__which is
 only set on powerpc hosts without FP registers:

 {{{
 root at atlantis:~# echo | gcc -E -dM -|grep -i FP
 #define __NO_FPRS__ 1
 root at atlantis:~# dpkg --print-architecture
 powerpcspe
 root at atlantis:~# uname -m
 ppc
 root at atlantis:~#
 }}}

 For reference, on a real powerpc host, the output is as follows:

 {{{
 (sid_powerpc-dchroot)glaubitz at partch:~$ echo | gcc -E -dM -|grep -i FP
 #define __FP_FAST_FMAF 1
 #define __FP_FAST_FMA 1
 (sid_powerpc-dchroot)glaubitz at partch:~$ dpkg --print-architecture
 powerpc
 (sid_powerpc-dchroot)glaubitz at partch:~$ uname -m
 ppc
 (sid_powerpc-dchroot)glaubitz at partch:~$
 }}}

 If you need any more input, please let me know.

 Adrian

--
Ticket URL: <http://ghc.haskell.org/trac/ghc/ticket/12075>
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