From e9af2cf3f16ab60b5c79ed91df95359b11784df6 Mon Sep 17 00:00:00 2001
From: Ben Gamari <ben@smart-cactus.org>
Date: Tue, 22 Aug 2023 13:26:58 -0400
Subject: [PATCH] llvmGen: Don't pass stack alignment via command line
As of https://reviews.llvm.org/D103048 LLVM no longer supports the
`-stack-alignment=...` flag. Instead this information is passed via a
module flag metadata node.
This requires dropping support for LLVM 11 and 12.
Fixes #23870
---
compiler/GHC/CmmToLlvm.hs | 29 ++++++++++++++++++++++++-
compiler/GHC/CmmToLlvm/Config.hs | 1 +
compiler/GHC/Driver/Config/CmmToLlvm.hs | 1 +
compiler/GHC/Driver/Pipeline/Execute.hs | 7 ------
configure.ac | 2 +-
5 files changed, 31 insertions(+), 9 deletions(-)
diff --git a/compiler/GHC/CmmToLlvm.hs b/compiler/GHC/CmmToLlvm.hs
index cfe32043b0d1..06936f4a4845 100644
--- a/compiler/GHC/CmmToLlvm.hs
+++ b/compiler/GHC/CmmToLlvm.hs
@@ -196,7 +196,7 @@ cmmLlvmGen _ = return ()
cmmMetaLlvmPrelude :: LlvmM ()
cmmMetaLlvmPrelude = do
- metas <- flip mapM stgTBAA $ \(uniq, name, parent) -> do
+ tbaa_metas <- flip mapM stgTBAA $ \(uniq, name, parent) -> do
-- Generate / lookup meta data IDs
tbaaId <- getMetaUniqueId
setUniqMeta uniq tbaaId
@@ -209,10 +209,37 @@ cmmMetaLlvmPrelude = do
-- just a name on its own. Previously `null` was accepted as the
-- name.
Nothing -> [ MetaStr name ]
+
+ platform <- getPlatform
+ cfg <- getConfig
+ let stack_alignment_metas =
+ case platformArch platform of
+ ArchX86_64 | llvmCgAvxEnabled cfg -> [mkStackAlignmentMeta 32]
+ _ -> []
+ module_flags_metas <- mkModuleFlagsMeta stack_alignment_metas
+ let metas = tbaa_metas ++ module_flags_metas
cfg <- getConfig
renderLlvm (ppLlvmMetas cfg metas)
(ppLlvmMetas cfg metas)
+mkNamedMeta :: LMString -> [MetaExpr] -> LlvmM [MetaDecl]
+mkNamedMeta name exprs = do
+ (ids, decls) <- unzip <$> mapM f exprs
+ return $ decls ++ [MetaNamed name ids]
+ where
+ f expr = do
+ i <- getMetaUniqueId
+ return (i, MetaUnnamed i expr)
+
+mkModuleFlagsMeta :: [ModuleFlag] -> LlvmM [MetaDecl]
+mkModuleFlagsMeta =
+ mkNamedMeta "llvm.module.flags" . map moduleFlagToMetaExpr
+
+mkStackAlignmentMeta :: Integer -> ModuleFlag
+mkStackAlignmentMeta alignment =
+ ModuleFlag MFBError "override-stack-alignment" (MetaLit $ LMIntLit alignment i32)
+
+
-- -----------------------------------------------------------------------------
-- | Marks variables as used where necessary
--
diff --git a/compiler/GHC/CmmToLlvm/Config.hs b/compiler/GHC/CmmToLlvm/Config.hs
index 649a33c2f67b..ecab7fdcc14b 100644
--- a/compiler/GHC/CmmToLlvm/Config.hs
+++ b/compiler/GHC/CmmToLlvm/Config.hs
@@ -36,6 +36,7 @@ data LlvmCgConfig = LlvmCgConfig
, llvmCgContext :: !SDocContext -- ^ Context for LLVM code generation
, llvmCgFillUndefWithGarbage :: !Bool -- ^ Fill undefined literals with garbage values
, llvmCgSplitSection :: !Bool -- ^ Split sections
+ , llvmCgAvxEnabled :: !Bool
, llvmCgBmiVersion :: Maybe BmiVersion -- ^ (x86) BMI instructions
, llvmCgLlvmVersion :: Maybe LlvmVersion -- ^ version of Llvm we're using
, llvmCgDoWarn :: !Bool -- ^ True ==> warn unsupported Llvm version
diff --git a/compiler/GHC/Driver/Config/CmmToLlvm.hs b/compiler/GHC/Driver/Config/CmmToLlvm.hs
index c71da60b4511..c0a21c9cb1f9 100644
--- a/compiler/GHC/Driver/Config/CmmToLlvm.hs
+++ b/compiler/GHC/Driver/Config/CmmToLlvm.hs
@@ -23,6 +23,7 @@ initLlvmCgConfig logger config_cache dflags = do
, llvmCgContext = initSDocContext dflags PprCode
, llvmCgFillUndefWithGarbage = gopt Opt_LlvmFillUndefWithGarbage dflags
, llvmCgSplitSection = gopt Opt_SplitSections dflags
+ , llvmCgAvxEnabled = isAvxEnabled dflags
, llvmCgBmiVersion = case platformArch (targetPlatform dflags) of
ArchX86_64 -> bmiVersion dflags
ArchX86 -> bmiVersion dflags
diff --git a/compiler/GHC/Driver/Pipeline/Execute.hs b/compiler/GHC/Driver/Pipeline/Execute.hs
index 4a1b50f1a6e1..0581930f4a40 100644
--- a/compiler/GHC/Driver/Pipeline/Execute.hs
+++ b/compiler/GHC/Driver/Pipeline/Execute.hs
@@ -948,8 +948,6 @@ llvmOptions llvm_config dflags =
[("-enable-tbaa -tbaa", "-enable-tbaa") | gopt Opt_LlvmTBAA dflags ]
++ [("-relocation-model=" ++ rmodel
,"-relocation-model=" ++ rmodel) | not (null rmodel)]
- ++ [("-stack-alignment=" ++ (show align)
- ,"-stack-alignment=" ++ (show align)) | align > 0 ]
-- Additional llc flags
++ [("", "-mcpu=" ++ mcpu) | not (null mcpu)
@@ -968,11 +966,6 @@ llvmOptions llvm_config dflags =
platform = targetPlatform dflags
- align :: Int
- align = case platformArch platform of
- ArchX86_64 | isAvxEnabled dflags -> 32
- _ -> 0
-
attrs :: String
attrs = intercalate "," $ mattr
++ ["+sse42" | isSse4_2Enabled dflags ]
diff --git a/configure.ac b/configure.ac
index 57a5c24b4faa..cc659add2aa8 100644
--- a/configure.ac
+++ b/configure.ac
@@ -539,7 +539,7 @@ AC_SUBST(InstallNameToolCmd)
# tools we are looking for. In the past, GHC supported a number of
# versions of LLVM simultaneously, but that stopped working around
# 3.5/3.6 release of LLVM.
-LlvmMinVersion=11 # inclusive
+LlvmMinVersion=13 # inclusive
LlvmMaxVersion=16 # not inclusive
AC_SUBST([LlvmMinVersion])
AC_SUBST([LlvmMaxVersion])
--
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