[WebAssembly] Make pthread imply bulk-memory, mutable-globals

[tlively]

Summary

This paves the way for using passive segments in pthread builds, which
will make separate memory files unnecessary. Mutable globals are also
necessary for the upcoming implementation of TLS.

[tlively]

• Add mutable-globals

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clang/lib/Driver/ToolChains/WebAssembly.cpp

 
 void WebAssembly::addClangTargetOptions(const ArgList &DriverArgs,
                                         ArgStringList &CC1Args,
                                         Action::OffloadKind) const {
   if (DriverArgs.hasFlag(clang::driver::options::OPT_fuse_init_array,
                          options::OPT_fno_use_init_array, true))
     CC1Args.push_back("-fuse-init-array");
 
-  // '-pthread' implies '-target-feature +atomics'
+  // '-pthread' implies target features atomics and bulk-memory
   if (DriverArgs.hasFlag(options::OPT_pthread, options::OPT_no_pthread,
                          false)) {
     if (DriverArgs.hasFlag(options::OPT_mno_atomics, options::OPT_matomics,
                            false))
       getDriver().Diag(diag::err_drv_argument_not_allowed_with)
           << "-pthread"
           << "-mno-atomics";
+    if (DriverArgs.hasFlag(options::OPT_mno_bulk_memory,
+                           options::OPT_mbulk_memory, false))
+      getDriver().Diag(diag::err_drv_argument_not_allowed_with)
+          << "-pthread"
+          << "-mno-bulk-memory";
     CC1Args.push_back("-target-feature");
     CC1Args.push_back("+atomics");
+    CC1Args.push_back("-target-feature");
+    CC1Args.push_back("+bulk-memory");
   }
 }
 
 ToolChain::RuntimeLibType WebAssembly::GetDefaultRuntimeLibType() const {
   return ToolChain::RLT_CompilerRT;
 }
 
 ToolChain::CXXStdlibType

clang/test/Driver/wasm-toolchain.c

 // A basic C compile command-line with known OS.
 
 // RUN: %clang -### -no-canonical-prefixes -target wasm32-wasi --sysroot=/foo %s 2>&1 \
 // RUN:   | FileCheck -check-prefix=COMPILE %s
 // COMPILE: clang{{.*}}" "-cc1" {{.*}} "-internal-isystem" "/foo/include/wasm32-wasi" "-internal-isystem" "/foo/include"
 
 // Thread-related command line tests.
 
-// '-pthread' sets '-target-feature +atomics' and '--shared-memory'
+// '-pthread' sets +atomics, +bulk-memory, and --shared-memory
 // RUN: %clang -### -no-canonical-prefixes -target wasm32-unknown-unknown \
 // RUN:    --sysroot=/foo %s -fuse-ld=wasm-ld -pthread 2>&1 \
 // RUN:  | FileCheck -check-prefix=PTHREAD %s
-// PTHREAD: clang{{.*}}" "-cc1" {{.*}} "-target-feature" "+atomics"
+// PTHREAD: clang{{.*}}" "-cc1" {{.*}} "-target-feature" "+atomics" "-target-feature" "+bulk-memory"
 // PTHREAD: wasm-ld{{.*}}" "-lpthread" "--shared-memory"
 
 // '-pthread' not allowed with '-mno-atomics'
 // RUN: %clang -### -no-canonical-prefixes -target wasm32-unknown-unknown \
 // RUN:     --sysroot=/foo %s -pthread -mno-atomics 2>&1 \
 // RUN:   | FileCheck -check-prefix=PTHREAD_NO_ATOMICS %s
 // PTHREAD_NO_ATOMICS: invalid argument '-pthread' not allowed with '-mno-atomics'
 
+// '-pthread' not allowed with '-mno-bulk-memory'
+// RUN: %clang -### -no-canonical-prefixes -target wasm32-unknown-unknown \
+// RUN:     --sysroot=/foo %s -pthread -mno-bulk-memory 2>&1 \
+// RUN:   | FileCheck -check-prefix=BULK_MEM_NO_ATOMICS %s
+// BULK_MEM_NO_ATOMICS: invalid argument '-pthread' not allowed with '-mno-bulk-memory'
+
 // RUN: %clang %s -### -fsanitize=address -target wasm32-unknown-emscripten 2>&1 | FileCheck -check-prefix=CHECK-ASAN-EMSCRIPTEN %s
 // CHECK-ASAN-EMSCRIPTEN: "-fsanitize=address"
 // CHECK-ASAN-EMSCRIPTEN: "-fsanitize-address-globals-dead-stripping"