Marge Bot pushed to branch master at Glasgow Haskell Compiler / GHC Commits: 414d1fe1 by Cheng Shao at 2026-01-06T19:39:20-05:00 compiler: fix LLVM backend pdep/pext handling for i386 target This patch fixes LLVM backend's pdep/pext handling for i386 target, and also removes non-existent 128/256/512 bit hs_pdep/hs_pext callees. See amended note for more explanation. Fixes #26450. Co-authored-by: Codex - - - - - c7f6fba3 by Cheng Shao at 2026-01-06T19:39:20-05:00 ci: remove allow_failure flag for i386 alpine job The LLVM codegen issue for i386 has been fixed, and the i386 alpine job should pass now. This commit removes the allow_failure flag so that other i386 regressions in the future are signaled more timely. - - - - - 3 changed files: - .gitlab/generate-ci/gen_ci.hs - .gitlab/jobs.yaml - compiler/GHC/CmmToLlvm/CodeGen.hs Changes: ===================================== .gitlab/generate-ci/gen_ci.hs ===================================== @@ -1250,7 +1250,7 @@ alpine_x86 = , fullyStaticBrokenTests (disableValidate (allowFailureGroup (standardBuildsWithConfig Amd64 (Linux Alpine312) staticNativeInt))) -- Dynamically linked build, suitable for building your own static executables on alpine , disableValidate (standardBuildsWithConfig Amd64 (Linux Alpine323) (splitSectionsBroken vanilla)) - , allowFailureGroup (standardBuildsWithConfig I386 (Linux Alpine323) (splitSectionsBroken vanilla)) + , standardBuildsWithConfig I386 (Linux Alpine323) (splitSectionsBroken vanilla) ] where -- ghcilink002 broken due to #17869 ===================================== .gitlab/jobs.yaml ===================================== @@ -484,7 +484,7 @@ ".gitlab/ci.sh clean", "cat ci_timings.txt" ], - "allow_failure": true, + "allow_failure": false, "artifacts": { "expire_in": "2 weeks", "paths": [ @@ -1155,7 +1155,7 @@ ".gitlab/ci.sh clean", "cat ci_timings.txt" ], - "allow_failure": true, + "allow_failure": false, "artifacts": { "expire_in": "8 weeks", "paths": [ @@ -4034,7 +4034,7 @@ ".gitlab/ci.sh clean", "cat ci_timings.txt" ], - "allow_failure": true, + "allow_failure": false, "artifacts": { "expire_in": "1 year", "paths": [ ===================================== compiler/GHC/CmmToLlvm/CodeGen.hs ===================================== @@ -248,6 +248,14 @@ Since x86 PDep/PExt instructions only exist for 32/64 bit widths we use the 32bit variant to compute the 8/16bit primops. To do so we extend/truncate the argument/result around the call. + +Note that the 64-bit intrinsics (`llvm.x86.bmi.pdep.64` and +`llvm.x86.bmi.pext.64`) are only legal on 64-bit x86 targets, not on +i386. Therefore on i386 we must fall back to the runtime helper +(`hs_pdep64`/`hs_pext64`) for the 64-bit primops. + +See https://github.com/llvm/llvm-project/issues/172857 for upstream +discussion about portable pdep/pext intrinsics. -} genCall (PrimTarget op@(MO_Pdep w)) [dst] args = do cfg <- getConfig @@ -970,36 +978,34 @@ cmmPrimOpFunctions mop = do W8 -> fsLit "llvm.x86.bmi.pdep.32" W16 -> fsLit "llvm.x86.bmi.pdep.32" W32 -> fsLit "llvm.x86.bmi.pdep.32" - W64 -> fsLit "llvm.x86.bmi.pdep.64" - W128 -> fsLit "llvm.x86.bmi.pdep.128" - W256 -> fsLit "llvm.x86.bmi.pdep.256" - W512 -> fsLit "llvm.x86.bmi.pdep.512" + W64 + | is32bit -> fsLit "hs_pdep64" + | otherwise -> fsLit "llvm.x86.bmi.pdep.64" + -- LLVM only provides x86 PDep/PExt intrinsics for 32/64 bits + _ -> unsupported | otherwise -> case w of W8 -> fsLit "hs_pdep8" W16 -> fsLit "hs_pdep16" W32 -> fsLit "hs_pdep32" W64 -> fsLit "hs_pdep64" - W128 -> fsLit "hs_pdep128" - W256 -> fsLit "hs_pdep256" - W512 -> fsLit "hs_pdep512" + _ -> unsupported MO_Pext w | isBmi2Enabled -> case w of -- See Note [LLVM PDep/PExt intrinsics] W8 -> fsLit "llvm.x86.bmi.pext.32" W16 -> fsLit "llvm.x86.bmi.pext.32" W32 -> fsLit "llvm.x86.bmi.pext.32" - W64 -> fsLit "llvm.x86.bmi.pext.64" - W128 -> fsLit "llvm.x86.bmi.pext.128" - W256 -> fsLit "llvm.x86.bmi.pext.256" - W512 -> fsLit "llvm.x86.bmi.pext.512" + W64 + | is32bit -> fsLit "hs_pext64" + | otherwise -> fsLit "llvm.x86.bmi.pext.64" + -- LLVM only provides x86 PDep/PExt intrinsics for 32/64 bits + _ -> unsupported | otherwise -> case w of W8 -> fsLit "hs_pext8" W16 -> fsLit "hs_pext16" W32 -> fsLit "hs_pext32" W64 -> fsLit "hs_pext64" - W128 -> fsLit "hs_pext128" - W256 -> fsLit "hs_pext256" - W512 -> fsLit "hs_pext512" + _ -> unsupported MO_AddIntC w -> case w of W8 -> fsLit "llvm.sadd.with.overflow.i8" View it on GitLab: https://gitlab.haskell.org/ghc/ghc/-/compare/4079dcd6418763f0a7b255d834c0353... -- View it on GitLab: https://gitlab.haskell.org/ghc/ghc/-/compare/4079dcd6418763f0a7b255d834c0353... You're receiving this email because of your account on gitlab.haskell.org.