Author: jroelofs Date: Wed Sep 6 10:09:25 2017 New Revision: 312651 URL: http://llvm.org/viewvc/llvm-project?rev=312651&view=rev Log: Fix ARM bare metal driver to support atomics
The new bare metal support only supports the single thread model. This causes the builtin atomic functions (e.g.: __atomic_fetch_add) to not generate thread-safe assembly for these operations, which breaks our firmware. We target bare metal, and need to atomically modify variables in our interrupt routines, and task threads. Internally, the -mthread-model flag determines whether to lower or expand atomic operations (see D4984). This change removes the overridden thread model methods, and instead relies on the base ToolChain class to validate the thread model (which already includes logic to validate single thread model support). If the single thread model is required, the -mthread-model flag will have to be provided. As a workaround "-mthread-model posix" could be provided, but it only works due to a bug in the validation of the -mthread-model flag (separate patch coming to fix this). https://reviews.llvm.org/D37493 Patch by: Ian Tessier! Modified: cfe/trunk/lib/Driver/ToolChains/BareMetal.cpp cfe/trunk/lib/Driver/ToolChains/BareMetal.h cfe/trunk/test/Driver/baremetal.cpp Modified: cfe/trunk/lib/Driver/ToolChains/BareMetal.cpp URL: http://llvm.org/viewvc/llvm-project/cfe/trunk/lib/Driver/ToolChains/BareMetal.cpp?rev=312651&r1=312650&r2=312651&view=diff ============================================================================== --- cfe/trunk/lib/Driver/ToolChains/BareMetal.cpp (original) +++ cfe/trunk/lib/Driver/ToolChains/BareMetal.cpp Wed Sep 6 10:09:25 2017 @@ -65,14 +65,6 @@ Tool *BareMetal::buildLinker() const { return new tools::baremetal::Linker(*this); } -std::string BareMetal::getThreadModel() const { - return "single"; -} - -bool BareMetal::isThreadModelSupported(const StringRef Model) const { - return Model == "single"; -} - std::string BareMetal::getRuntimesDir() const { SmallString<128> Dir(getDriver().ResourceDir); llvm::sys::path::append(Dir, "lib", "baremetal"); Modified: cfe/trunk/lib/Driver/ToolChains/BareMetal.h URL: http://llvm.org/viewvc/llvm-project/cfe/trunk/lib/Driver/ToolChains/BareMetal.h?rev=312651&r1=312650&r2=312651&view=diff ============================================================================== --- cfe/trunk/lib/Driver/ToolChains/BareMetal.h (original) +++ cfe/trunk/lib/Driver/ToolChains/BareMetal.h Wed Sep 6 10:09:25 2017 @@ -38,8 +38,6 @@ public: bool isPICDefaultForced() const override { return false; } bool SupportsProfiling() const override { return false; } bool SupportsObjCGC() const override { return false; } - std::string getThreadModel() const override; - bool isThreadModelSupported(const StringRef Model) const override; RuntimeLibType GetDefaultRuntimeLibType() const override { return ToolChain::RLT_CompilerRT; Modified: cfe/trunk/test/Driver/baremetal.cpp URL: http://llvm.org/viewvc/llvm-project/cfe/trunk/test/Driver/baremetal.cpp?rev=312651&r1=312650&r2=312651&view=diff ============================================================================== --- cfe/trunk/test/Driver/baremetal.cpp (original) +++ cfe/trunk/test/Driver/baremetal.cpp Wed Sep 6 10:09:25 2017 @@ -74,4 +74,12 @@ // RUN: %clangxx -target arm-none-eabi -v 2>&1 \ // RUN: | FileCheck %s --check-prefix=CHECK-THREAD-MODEL -// CHECK-THREAD-MODEL: Thread model: single +// CHECK-THREAD-MODEL: Thread model: posix + +// RUN: %clangxx -target arm-none-eabi -mthread-model single -v 2>&1 \ +// RUN: | FileCheck %s --check-prefix=CHECK-THREAD-MODEL-SINGLE +// CHECK-THREAD-MODEL-SINGLE: Thread model: single + +// RUN: %clangxx -target arm-none-eabi -mthread-model posix -v 2>&1 \ +// RUN: | FileCheck %s --check-prefix=CHECK-THREAD-MODEL-POSIX +// CHECK-THREAD-MODEL-POSIX: Thread model: posix _______________________________________________ cfe-commits mailing list cfe-commits@lists.llvm.org http://lists.llvm.org/cgi-bin/mailman/listinfo/cfe-commits
