https://github.com/statham-arm updated https://github.com/llvm/llvm-project/pull/97827
>From 81d77bf87dd47684683492ab70cc45ab6eb4364e Mon Sep 17 00:00:00 2001 From: Simon Tatham <simon.tat...@arm.com> Date: Fri, 5 Jul 2024 11:57:19 +0100 Subject: [PATCH] [Clang][Driver] Skip empty strings in getAArch64MultilibFlags In a multilib setting, if you compile with a command line such as `clang --target=aarch64-none-elf -march=armv8.9-a+rcpc3`, `getAArch64MultilibFlags` returns an ill-formed string containing two consecutive `+` signs, of the form `...+rcpc++rcpc3+...`, causing later stages of multilib selection to get confused. The `++` arises from the entry in `AArch64::Extensions` for the SubtargetFeature `rcpc-immo`, which is a dependency of the `rcpc3` SubtargetFeature, but doesn't have an _extension_ name for the purposes of the `-march=foo+bar` option. So its `UserVisibleName` field is the empty string. To fix this, I've excluded extensions from consideration in `getAArch64MultilibFlags` if they have an empty `UserVisibleName`. Since the input to this function is not derived from a completely general set of SubtargetFeatures, but from a set that has only just been converted _from_ a clang driver command line, the only extensions skipped by this check should be cases like this one, where the anonymous extension was only included because it was a dependency of one mentioned explicitly. I've also made the analogous change in `getARMMultilibFlags`. I don't think it's necessary right now, because the architecture extensions for ARM (defined in `ARMTargetParser.def` rather than Tablegen) don't include any anonymous ones. But it seems sensible to add the check anyway, in case future refactoring introduces anonymous array elements in the same way that AArch64 did, and also in case someone writes a function for another platform by using either of these as example code. --- clang/lib/Driver/ToolChain.cpp | 20 ++++++++++++-------- clang/test/Driver/aarch64-multilib-rcpc3.c | 4 ++++ 2 files changed, 16 insertions(+), 8 deletions(-) create mode 100644 clang/test/Driver/aarch64-multilib-rcpc3.c diff --git a/clang/lib/Driver/ToolChain.cpp b/clang/lib/Driver/ToolChain.cpp index 977e08390800d7..85ae4d2a26fee2 100644 --- a/clang/lib/Driver/ToolChain.cpp +++ b/clang/lib/Driver/ToolChain.cpp @@ -195,11 +195,13 @@ static void getAArch64MultilibFlags(const Driver &D, UnifiedFeatures.end()); std::vector<std::string> MArch; for (const auto &Ext : AArch64::Extensions) - if (FeatureSet.contains(Ext.PosTargetFeature)) - MArch.push_back(Ext.UserVisibleName.str()); + if (!Ext.UserVisibleName.empty()) + if (FeatureSet.contains(Ext.PosTargetFeature)) + MArch.push_back(Ext.UserVisibleName.str()); for (const auto &Ext : AArch64::Extensions) - if (FeatureSet.contains(Ext.NegTargetFeature)) - MArch.push_back(("no" + Ext.UserVisibleName).str()); + if (!Ext.UserVisibleName.empty()) + if (FeatureSet.contains(Ext.NegTargetFeature)) + MArch.push_back(("no" + Ext.UserVisibleName).str()); StringRef ArchName; for (const auto &ArchInfo : AArch64::ArchInfos) if (FeatureSet.contains(ArchInfo->ArchFeature)) @@ -221,11 +223,13 @@ static void getARMMultilibFlags(const Driver &D, UnifiedFeatures.end()); std::vector<std::string> MArch; for (const auto &Ext : ARM::ARCHExtNames) - if (FeatureSet.contains(Ext.Feature)) - MArch.push_back(Ext.Name.str()); + if (!Ext.Name.empty()) + if (FeatureSet.contains(Ext.Feature)) + MArch.push_back(Ext.Name.str()); for (const auto &Ext : ARM::ARCHExtNames) - if (FeatureSet.contains(Ext.NegFeature)) - MArch.push_back(("no" + Ext.Name).str()); + if (!Ext.Name.empty()) + if (FeatureSet.contains(Ext.NegFeature)) + MArch.push_back(("no" + Ext.Name).str()); MArch.insert(MArch.begin(), ("-march=" + Triple.getArchName()).str()); Result.push_back(llvm::join(MArch, "+")); diff --git a/clang/test/Driver/aarch64-multilib-rcpc3.c b/clang/test/Driver/aarch64-multilib-rcpc3.c new file mode 100644 index 00000000000000..b839079e0442d6 --- /dev/null +++ b/clang/test/Driver/aarch64-multilib-rcpc3.c @@ -0,0 +1,4 @@ +// RUN: %clang --target=aarch64-none-elf -march=armv8.9-a+rcpc3 -print-multi-flags-experimental -c %s 2>&1 | FileCheck %s + +// CHECK: -march=armv8.9-a +// CHECK-SAME: +rcpc+rcpc3+ _______________________________________________ cfe-commits mailing list cfe-commits@lists.llvm.org https://lists.llvm.org/cgi-bin/mailman/listinfo/cfe-commits