[clang] a6aae5f - [WebAssembly] Don't inline -emscripten-cxx-exceptions-allowed functions
Heejin Ahn via cfe-commits
cfe-commits at lists.llvm.org
Wed Mar 24 12:28:24 PDT 2021
Author: Heejin Ahn
Date: 2021-03-24T12:27:49-07:00
New Revision: a6aae5f7fcd1111db87bfe77072912484213f872
URL: https://github.com/llvm/llvm-project/commit/a6aae5f7fcd1111db87bfe77072912484213f872
DIFF: https://github.com/llvm/llvm-project/commit/a6aae5f7fcd1111db87bfe77072912484213f872.diff
LOG: [WebAssembly] Don't inline -emscripten-cxx-exceptions-allowed functions
Functions specified in `-emscripten-cxx-exceptions-allowed`, which is
set by Emscripten's `EXCEPTION_CATCHING_ALLOWED` setting, can be inlined
in LLVM middle ends before we reach WebAssemblyLowerEmscriptenEHSjLj
pass in the wasm backend and thus don't get transformed for exception
catching.
This fixes the issue by adding `--force-attribute=FUNC_NAME:noinline`
for each function name in `-emscripten-cxx-exceptions-allowed`, which
adds `noinline` attribute to the specified function and thus excludes
the function from inlining candidates in optimization passes.
Fixes the remaining half of
https://github.com/emscripten-core/emscripten/issues/10721.
Reviewed By: sbc100
Differential Revision: https://reviews.llvm.org/D99259
Added:
Modified:
clang/lib/Driver/ToolChains/WebAssembly.cpp
clang/test/Driver/wasm-toolchain.c
Removed:
################################################################################
diff --git a/clang/lib/Driver/ToolChains/WebAssembly.cpp b/clang/lib/Driver/ToolChains/WebAssembly.cpp
index 8c4d99b8ad07..e1ca90b195e2 100644
--- a/clang/lib/Driver/ToolChains/WebAssembly.cpp
+++ b/clang/lib/Driver/ToolChains/WebAssembly.cpp
@@ -294,6 +294,36 @@ void WebAssembly::addClangTargetOptions(const ArgList &DriverArgs,
CC1Args.push_back("-target-feature");
CC1Args.push_back("+exception-handling");
}
+
+ for (const Arg *A : DriverArgs.filtered(options::OPT_mllvm)) {
+ StringRef Opt = A->getValue(0);
+ if (Opt.startswith("-emscripten-cxx-exceptions-allowed")) {
+ // '-mllvm -emscripten-cxx-exceptions-allowed' should be used with
+ // '-mllvm -enable-emscripten-cxx-exceptions'
+ bool EmExceptionArgExists = false;
+ for (const Arg *A : DriverArgs.filtered(options::OPT_mllvm)) {
+ if (StringRef(A->getValue(0)) == "-enable-emscripten-cxx-exceptions") {
+ EmExceptionArgExists = true;
+ break;
+ }
+ }
+ if (!EmExceptionArgExists)
+ getDriver().Diag(diag::err_drv_argument_only_allowed_with)
+ << "-mllvm -emscripten-cxx-exceptions-allowed"
+ << "-mllvm -enable-emscripten-cxx-exceptions";
+
+ // Prevent functions specified in -emscripten-cxx-exceptions-allowed list
+ // from being inlined before reaching the wasm backend.
+ StringRef FuncNamesStr = Opt.split('=').second;
+ SmallVector<StringRef, 4> FuncNames;
+ FuncNamesStr.split(FuncNames, ',');
+ for (auto Name : FuncNames) {
+ CC1Args.push_back("-mllvm");
+ CC1Args.push_back(DriverArgs.MakeArgString("--force-attribute=" + Name +
+ ":noinline"));
+ }
+ }
+ }
}
ToolChain::RuntimeLibType WebAssembly::GetDefaultRuntimeLibType() const {
diff --git a/clang/test/Driver/wasm-toolchain.c b/clang/test/Driver/wasm-toolchain.c
index 17037819cfda..d2e6de4667ac 100644
--- a/clang/test/Driver/wasm-toolchain.c
+++ b/clang/test/Driver/wasm-toolchain.c
@@ -79,6 +79,21 @@
// RUN: | FileCheck -check-prefix=PTHREAD_NO_SIGN_EXT %s
// PTHREAD_NO_SIGN_EXT: invalid argument '-pthread' not allowed with '-mno-sign-ext'
+// '-mllvm -emscripten-cxx-exceptions-allowed=foo,bar' sets
+// '-mllvm --force-attribute=foo:noinline -mllvm --force-attribute=bar:noinline'
+// RUN: %clang -### -no-canonical-prefixes -target wasm32-unknown-unknown \
+// RUN: --sysroot=/foo %s -mllvm -enable-emscripten-cxx-exceptions \
+// RUN: -mllvm -emscripten-cxx-exceptions-allowed=foo,bar 2>&1 \
+// RUN: | FileCheck -check-prefix=EMSCRIPTEN_EH_ALLOWED_NOINLINE %s
+// EMSCRIPTEN_EH_ALLOWED_NOINLINE: clang{{.*}}" "-cc1" {{.*}} "-mllvm" "--force-attribute=foo:noinline" "-mllvm" "--force-attribute=bar:noinline"
+
+// '-mllvm -emscripten-cxx-exceptions-allowed' only allowed with
+// '-mllvm -enable-emscripten-cxx-exceptions'
+// RUN: %clang -### -no-canonical-prefixes -target wasm32-unknown-unknown \
+// RUN: --sysroot=/foo %s -mllvm -emscripten-cxx-exceptions-allowed 2>&1 \
+// RUN: | FileCheck -check-prefix=EMSCRIPTEN_EH_ALLOWED_WO_ENABLE %s
+// EMSCRIPTEN_EH_ALLOWED_WO_ENABLE: invalid argument '-mllvm -emscripten-cxx-exceptions-allowed' only allowed with '-mllvm -enable-emscripten-cxx-exceptions'
+
// '-fwasm-exceptions' sets +exception-handling
// RUN: %clang -### -no-canonical-prefixes -target wasm32-unknown-unknown \
// RUN: --sysroot=/foo %s -fwasm-exceptions 2>&1 \
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