#10870: PPC.Ppr: Shift by 32 bits is not allowed. ---------------------------------------+---------------------------------- Reporter: nomeata | Owner: Type: bug | Status: new Priority: normal | Milestone: Component: Compiler (CodeGen) | Version: 7.10.2 Resolution: | Keywords: Operating System: Unknown/Multiple | Architecture: powerpc Type of failure: None/Unknown | Test Case: Blocked By: | Blocking: Related Tickets: | Differential Revisions: ---------------------------------------+---------------------------------- Comment (by erikd): Maybe adding the panic was the wrong thing to do there. On 32 bit PowerPC, a right shift of 32 bits should just result in zero. However, the PowerPC codegen now supports 64 bit PowerPC, so we need to be careful. -- Ticket URL: http://ghc.haskell.org/trac/ghc/ticket/10870#comment:1 GHC http://www.haskell.org/ghc/ The Glasgow Haskell Compiler

#10870: PPC.Ppr: Shift by 32 bits is not allowed. ---------------------------------------+---------------------------------- Reporter: nomeata | Owner: Type: bug | Status: new Priority: normal | Milestone: Component: Compiler (CodeGen) | Version: 7.10.2 Resolution: | Keywords: Operating System: Unknown/Multiple | Architecture: powerpc Type of failure: None/Unknown | Test Case: Blocked By: | Blocking: Related Tickets: | Differential Revisions: ---------------------------------------+---------------------------------- Comment (by erikd): I'm currently working on the ghc-7.10 branch because the master branch currently does not compile on PowerPC due to #7830. I have a test program: {{{ import Data.Bits import Data.Int import Data.Word shift32R :: (Bits a, Num a) => a -> a shift32R x = unsafeShiftR x 32 main :: IO () main = do print $ map shift32R [ 123456, 0x7fffffff :: Int ] print $ map shift32R [ 123456, 0xffffffff :: Word ] print $ map shift32R [ 123456678, 123456678123456678 :: Int64 ] print $ map shift32R [ 123456678, 123456678123456678 :: Word64 ] }}} and I have a fix that seems to work (PowerPC output is same as for x86_64 and Arm), but the compiler prints 14 identical instances of the warning: {{{ WARNING: file compiler/simplCore/SimplEnv.hs, line 530 showl_a1O5 }}} -- Ticket URL: http://ghc.haskell.org/trac/ghc/ticket/10870#comment:3 GHC http://www.haskell.org/ghc/ The Glasgow Haskell Compiler

#10870: PPC.Ppr: Shift by 32 bits is not allowed. ---------------------------------------+---------------------------------- Reporter: nomeata | Owner: Type: bug | Status: new Priority: normal | Milestone: Component: Compiler (CodeGen) | Version: 7.10.2 Resolution: | Keywords: Operating System: Unknown/Multiple | Architecture: powerpc Type of failure: None/Unknown | Test Case: Blocked By: | Blocking: Related Tickets: | Differential Rev(s): Phab:D1322 Wiki Page: | ---------------------------------------+---------------------------------- Changes (by erikd): * differential: => Phab:D1322 -- Ticket URL: http://ghc.haskell.org/trac/ghc/ticket/10870#comment:5 GHC http://www.haskell.org/ghc/ The Glasgow Haskell Compiler

#10870: PPC.Ppr: Shift by 32 bits is not allowed. ---------------------------------------+---------------------------------- Reporter: nomeata | Owner: Type: bug | Status: merge Priority: normal | Milestone: Component: Compiler (CodeGen) | Version: 7.10.2 Resolution: | Keywords: Operating System: Unknown/Multiple | Architecture: powerpc Type of failure: None/Unknown | Test Case: Blocked By: | Blocking: Related Tickets: | Differential Rev(s): Phab:D1322 Wiki Page: | ---------------------------------------+---------------------------------- Changes (by erikd): * status: new => merge -- Ticket URL: http://ghc.haskell.org/trac/ghc/ticket/10870#comment:7 GHC http://www.haskell.org/ghc/ The Glasgow Haskell Compiler

#10870: PPC.Ppr: Shift by 32 bits is not allowed. ---------------------------------------+---------------------------------- Reporter: nomeata | Owner: Type: bug | Status: merge Priority: normal | Milestone: 7.10.3 Component: Compiler (CodeGen) | Version: 7.10.2 Resolution: | Keywords: Operating System: Unknown/Multiple | Architecture: powerpc Type of failure: None/Unknown | Test Case: Blocked By: | Blocking: Related Tickets: | Differential Rev(s): Phab:D1322 Wiki Page: | ---------------------------------------+---------------------------------- Changes (by erikd): * Attachment "0001-PPC-Fix-right-shift-by-32-bits-10870.patch" added. Patch for 7.10 branch -- Ticket URL: http://ghc.haskell.org/trac/ghc/ticket/10870 GHC http://www.haskell.org/ghc/ The Glasgow Haskell Compiler

#10870: PPC.Ppr: Shift by 32 bits is not allowed. ---------------------------------------+---------------------------------- Reporter: nomeata | Owner: Type: bug | Status: merge Priority: normal | Milestone: 7.10.3 Component: Compiler (CodeGen) | Version: 7.10.2 Resolution: | Keywords: Operating System: Unknown/Multiple | Architecture: powerpc Type of failure: None/Unknown | Test Case: Blocked By: | Blocking: Related Tickets: | Differential Rev(s): Phab:D1322 Wiki Page: | ---------------------------------------+---------------------------------- Comment (by trommler): Replying to [comment:9 erikd]:

The commit in the `master` branch doesn't apply to the `7.10` branch because of all the `powerpc64el` work in `master`. Speaking of 64-bit: I suppose I should implement shifts by 64 bit in a similar fashion for 64-bit PowerPC. I'll create a new ticket for that.

-- Ticket URL: http://ghc.haskell.org/trac/ghc/ticket/10870#comment:10 GHC http://www.haskell.org/ghc/ The Glasgow Haskell Compiler

#10870: PPC.Ppr: Shift by 32 bits is not allowed. ---------------------------------------+---------------------------------- Reporter: nomeata | Owner: Type: bug | Status: new Priority: normal | Milestone: 7.10.3 Component: Compiler (CodeGen) | Version: 7.10.2 Resolution: | Keywords: Operating System: Unknown/Multiple | Architecture: powerpc Type of failure: None/Unknown | Test Case: Blocked By: | Blocking: Related Tickets: | Differential Rev(s): Phab:D1322 Wiki Page: | ---------------------------------------+---------------------------------- Changes (by nomeata): * status: closed => new * resolution: fixed => Comment: Sorry to be the bringer of bad news, but this seems to be still occurring in 7.10.3-rc1: https://buildd.debian.org/status/fetch.php?pkg=haskell-vector- algorithms&arch=powerpc&ver=0.7.0.1-2&stamp=1446804253 -- Ticket URL: http://ghc.haskell.org/trac/ghc/ticket/10870#comment:12 GHC http://www.haskell.org/ghc/ The Glasgow Haskell Compiler

#10870: PPC.Ppr: Shift by 32 bits is not allowed. ---------------------------------------+---------------------------------- Reporter: nomeata | Owner: Type: bug | Status: infoneeded Priority: normal | Milestone: 7.10.3 Component: Compiler (CodeGen) | Version: 7.10.2 Resolution: | Keywords: Operating System: Unknown/Multiple | Architecture: powerpc Type of failure: None/Unknown | Test Case: Blocked By: | Blocking: Related Tickets: | Differential Rev(s): Phab:D1322 Wiki Page: | ---------------------------------------+---------------------------------- Changes (by trommler): * status: new => infoneeded Comment: Replying to [comment:12 nomeata]:

Sorry to be the bringer of bad news, but this seems to be still occurring in 7.10.3-rc1:

https://buildd.debian.org/status/fetch.php?pkg=haskell-vector- algorithms&arch=powerpc&ver=0.7.0.1-2&stamp=1446804253 Can you try the above patch (0001-PPC-nativeGen-fix-shift-right- arithmetic-31-bit.patch)?

I could only eye-ball the code (no 32 bit installation here), but I am pretty sure this is the only case left that triggers the panic you are seeing. -- Ticket URL: http://ghc.haskell.org/trac/ghc/ticket/10870#comment:13 GHC http://www.haskell.org/ghc/ The Glasgow Haskell Compiler

#10870: PPC.Ppr: Shift by 32 bits is not allowed. ---------------------------------------+---------------------------------- Reporter: nomeata | Owner: Type: bug | Status: infoneeded Priority: normal | Milestone: 7.10.3 Component: Compiler (CodeGen) | Version: 7.10.2 Resolution: | Keywords: Operating System: Unknown/Multiple | Architecture: powerpc Type of failure: None/Unknown | Test Case: Blocked By: | Blocking: Related Tickets: | Differential Rev(s): Phab:D1322 Wiki Page: | ---------------------------------------+---------------------------------- Changes (by trommler): * Attachment "0001-PPC-nativeGen-fix-shift-right-arithmetic-31-bit.patch" added. ...and for arithmetic right shifts -- Ticket URL: http://ghc.haskell.org/trac/ghc/ticket/10870 GHC http://www.haskell.org/ghc/ The Glasgow Haskell Compiler

Thanks! I almost kicked off a full ghc package upload to Debian, but I better wait until you have reached the final version of your patch. (Interesting that trac does not display your updates to the patch, this might be very confusion when people talk about different instances of a

#10870: PPC.Ppr: Shift by 32 bits is not allowed. ---------------------------------------+---------------------------------- Reporter: nomeata | Owner: Type: bug | Status: infoneeded Priority: normal | Milestone: 7.10.3 Component: Compiler (CodeGen) | Version: 7.10.2 Resolution: | Keywords: Operating System: Unknown/Multiple | Architecture: powerpc Type of failure: None/Unknown | Test Case: Blocked By: | Blocking: Related Tickets: | Differential Rev(s): Phab:D1322 Wiki Page: | ---------------------------------------+---------------------------------- Comment (by trommler): Replying to [comment:14 nomeata]: patch.) Sorry about that! I forgot to refresh the patch and uploaded an old version that did not even compile three times. I used the replace attachment option for each upload. -- Ticket URL: http://ghc.haskell.org/trac/ghc/ticket/10870#comment:15 GHC http://www.haskell.org/ghc/ The Glasgow Haskell Compiler

#10870: PPC.Ppr: Shift by 32 bits is not allowed. ---------------------------------------+---------------------------------- Reporter: nomeata | Owner: Type: bug | Status: merge Priority: normal | Milestone: 7.10.3 Component: Compiler (CodeGen) | Version: 7.10.2 Resolution: | Keywords: Operating System: Unknown/Multiple | Architecture: powerpc Type of failure: None/Unknown | Test Case: Blocked By: | Blocking: Related Tickets: | Differential Rev(s): Phab:D1322 Wiki Page: | ---------------------------------------+---------------------------------- Comment (by nomeata): Yay, vector-algorithms built now on powerpc! -- Ticket URL: http://ghc.haskell.org/trac/ghc/ticket/10870#comment:17 GHC http://www.haskell.org/ghc/ The Glasgow Haskell Compiler

#10870: PPC.Ppr: Shift by 32 bits is not allowed. ---------------------------------------+---------------------------------- Reporter: nomeata | Owner: Type: bug | Status: merge Priority: normal | Milestone: 7.10.3 Component: Compiler (CodeGen) | Version: 7.10.2 Resolution: | Keywords: Operating System: Unknown/Multiple | Architecture: powerpc Type of failure: None/Unknown | Test Case: Blocked By: | Blocking: Related Tickets: | Differential Rev(s): Phab:D1322 Wiki Page: | ---------------------------------------+---------------------------------- Comment (by nomeata): No, passes everywhere. But given the large output of the test suite, this sounds like https://github.com/haskell/cabal/issues/2398. Try to add the patch from https://github.com/haskell/cabal/pull/2913 and add `--show- details=direct`. -- Ticket URL: http://ghc.haskell.org/trac/ghc/ticket/10870#comment:19 GHC http://www.haskell.org/ghc/ The Glasgow Haskell Compiler

#10870: PPC.Ppr: Shift by 32 bits is not allowed. -------------------------------------+------------------------------------- Reporter: nomeata | Owner: Type: bug | Status: merge Priority: normal | Milestone: 7.10.3 Component: Compiler | Version: 7.10.2 (CodeGen) | Resolution: | Keywords: Operating System: Unknown/Multiple | Architecture: powerpc Type of failure: None/Unknown | Test Case: Blocked By: | Blocking: Related Tickets: | Differential Rev(s): Phab:D1322, Wiki Page: | Phab:1459 -------------------------------------+------------------------------------- Comment (by Ben Gamari ): In [changeset:"fb0d5120d383324c6934144b938525378e3ade75/ghc" fb0d512/ghc]: {{{ #!CommitTicketReference repository="ghc" revision="fb0d5120d383324c6934144b938525378e3ade75" nativeGen.PPC: Fix shift arith. right > 31 bits Arithmetic right shifts of more than 31 bits set all bits to the sign bit on PowerPC. iThe assembler does not allow shift amounts larger than 32 so do an arithemetic right shift of 31 bit instead. Fixes #10870 Test Plan: validate (especially on powerpc) Reviewers: austin, erikd, bgamari Reviewed By: bgamari Subscribers: thomie Differential Revision: https://phabricator.haskell.org/D1459 GHC Trac Issues: #10870 }}} -- Ticket URL: http://ghc.haskell.org/trac/ghc/ticket/10870#comment:21 GHC http://www.haskell.org/ghc/ The Glasgow Haskell Compiler