[WebAssembly] -pthread implies -target-feature +sign-ext

[tlively]

Summary

The sign extension proposal was motivated by a desire to not have
separate sign-extending atomic operations, so it is meant to be
enabled when threads are used.

[dschuff]

clang/test/Driver/wasm-toolchain.c

76

-mno-sign-ext

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 atomics, bulk-memory, and mutable-globals
+  // '-pthread' implies atomics, bulk-memory, mutable-globals, and sign-ext
   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";
     if (DriverArgs.hasFlag(options::OPT_mno_mutable_globals,
                            options::OPT_mmutable_globals, false))
       getDriver().Diag(diag::err_drv_argument_not_allowed_with)
           << "-pthread"
           << "-mno-mutable-globals";
+    if (DriverArgs.hasFlag(options::OPT_mno_sign_ext, options::OPT_msign_ext,
+                           false))
+      getDriver().Diag(diag::err_drv_argument_not_allowed_with)
+          << "-pthread"
+          << "-mno-sign-ext";
     CC1Args.push_back("-target-feature");
     CC1Args.push_back("+atomics");
     CC1Args.push_back("-target-feature");
     CC1Args.push_back("+bulk-memory");
     CC1Args.push_back("-target-feature");
     CC1Args.push_back("+mutable-globals");
+    CC1Args.push_back("-target-feature");
+    CC1Args.push_back("+sign-ext");
   }
 
   if (DriverArgs.getLastArg(options::OPT_fwasm_exceptions)) {
     // '-fwasm-exceptions' is not compatible with '-mno-exception-handling'
     if (DriverArgs.hasFlag(options::OPT_mno_exception_handing,
                            options::OPT_mexception_handing, false))
       getDriver().Diag(diag::err_drv_argument_not_allowed_with)
           << "-fwasm-exceptions"

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 +atomics, +bulk-memory, +mutable-globals, and --shared-memory
+// '-pthread' sets +atomics, +bulk-memory, +mutable-globals, +sign-ext, 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" "-target-feature" "+bulk-memory" "-target-feature" "+mutable-globals"
+// PTHREAD: clang{{.*}}" "-cc1" {{.*}} "-target-feature" "+atomics" "-target-feature" "+bulk-memory" "-target-feature" "+mutable-globals" "-target-feature" "+sign-ext"
 // 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=PTHREAD_NO_BULK_MEM %s
 // PTHREAD_NO_BULK_MEM: invalid argument '-pthread' not allowed with '-mno-bulk-memory'
 
 // '-pthread' not allowed with '-mno-mutable-globals'
 // RUN: %clang -### -no-canonical-prefixes -target wasm32-unknown-unknown \
 // RUN:     --sysroot=/foo %s -pthread -mno-mutable-globals 2>&1 \
 // RUN:   | FileCheck -check-prefix=PTHREAD_NO_MUT_GLOBALS %s
 // PTHREAD_NO_MUT_GLOBALS: invalid argument '-pthread' not allowed with '-mno-mutable-globals'
 
+// '-pthread' not allowed with '-mno-mutable-globals'
+// RUN: %clang -### -no-canonical-prefixes -target wasm32-unknown-unknown \
+// RUN:     --sysroot=/foo %s -pthread -mno-sign-ext 2>&1 \
+// RUN:   | FileCheck -check-prefix=PTHREAD_NO_SIGN_EXT %s
+// PTHREAD_NO_SIGN_EXT: invalid argument '-pthread' not allowed with '-mno-sign-ext'
+
 // '-fwasm-exceptions' sets +exception-handling
 // RUN: %clang -### -no-canonical-prefixes -target wasm32-unknown-unknown \
 // RUN:    --sysroot=/foo %s -fwasm-exceptions 2>&1 \
 // RUN:  | FileCheck -check-prefix=WASM_EXCEPTIONS %s
 // WASM_EXCEPTIONS: clang{{.*}}" "-cc1" {{.*}} "-target-feature" "+exception-handling"
 
 // '-fwasm-exceptions' not allowed with '-mno-exception-handling'
 // RUN: %clang -### -no-canonical-prefixes -target wasm32-unknown-unknown \