Swift Basic/Driver recognizes OpenBSD.

Add the platform conditional and set up other basics for the toolchain.

The ConditionalCompilation tests are updated to match, since otherwise
they seem to trip when building on non-OpenBSD platforms. The
Driver/linker test is updated to ensure lld is passed on this platform.
Note that OpenBSD calls "x86_64" as "amd64", so we use that name for the
architecture instead of trying to alias one to the other, as this makes
things simpler.

Author: 3405691582

lib/Basic/LangOptions.cpp

@@ -45,6 +45,7 @@ static const SupportedConditionalValue SupportedConditionalCompilationOSs[] = {
   "iOS",
   "Linux",
   "FreeBSD",
+  "OpenBSD",
   "Windows",
   "Android",
   "PS4",
@@ -258,6 +259,9 @@ std::pair<bool, bool> LangOptions::setTarget(llvm::Triple triple) {
   case llvm::Triple::FreeBSD:
     addPlatformConditionValue(PlatformConditionKind::OS, "FreeBSD");
     break;
+  case llvm::Triple::OpenBSD:
+    addPlatformConditionValue(PlatformConditionKind::OS, "OpenBSD");
+    break;
   case llvm::Triple::Win32:
     if (Target.getEnvironment() == llvm::Triple::Cygnus)
       addPlatformConditionValue(PlatformConditionKind::OS, "Cygwin");

lib/Basic/Platform.cpp

@@ -180,7 +180,6 @@ StringRef swift::getPlatformNameForTriple(const llvm::Triple &triple) {
   case llvm::Triple::KFreeBSD:
   case llvm::Triple::Lv2:
   case llvm::Triple::NetBSD:
-  case llvm::Triple::OpenBSD:
   case llvm::Triple::Solaris:
   case llvm::Triple::Minix:
   case llvm::Triple::RTEMS:
@@ -207,6 +206,8 @@ StringRef swift::getPlatformNameForTriple(const llvm::Triple &triple) {
     return triple.isAndroid() ? "android" : "linux";
   case llvm::Triple::FreeBSD:
     return "freebsd";
+  case llvm::Triple::OpenBSD:
+    return "openbsd";
   case llvm::Triple::Win32:
     switch (triple.getEnvironment()) {
     case llvm::Triple::Cygnus:

lib/Driver/Driver.cpp

@@ -267,6 +267,8 @@ Driver::buildToolChain(const llvm::opt::InputArgList &ArgList) {
     return std::make_unique<toolchains::GenericUnix>(*this, target);
   case llvm::Triple::FreeBSD:
     return std::make_unique<toolchains::GenericUnix>(*this, target);
+  case llvm::Triple::OpenBSD:
+    return std::make_unique<toolchains::OpenBSD>(*this, target);
   case llvm::Triple::Win32:
     if (target.isWindowsCygwinEnvironment())
       return std::make_unique<toolchains::Cygwin>(*this, target);

lib/Driver/ToolChains.h

@@ -157,6 +157,16 @@ class LLVM_LIBRARY_VISIBILITY Cygwin : public GenericUnix {
   ~Cygwin() = default;
 };
 
+class LLVM_LIBRARY_VISIBILITY OpenBSD : public GenericUnix {
+protected:
+  std::string getDefaultLinker() const override;
+
+public:
+  OpenBSD(const Driver &D, const llvm::Triple &Triple)
+      : GenericUnix(D, Triple) {}
+  ~OpenBSD() = default;
+};
+
 } // end namespace toolchains
 } // end namespace driver
 } // end namespace swift

lib/Driver/UnixToolChains.cpp

@@ -389,3 +389,7 @@ std::string toolchains::Cygwin::getDefaultLinker() const {
 }
 
 std::string toolchains::Cygwin::getTargetForLinker() const { return ""; }
+
+std::string toolchains::OpenBSD::getDefaultLinker() const {
+  return "lld";
+}

test/Driver/linker.swift

@@ -37,6 +37,9 @@
 // RUN: %swiftc_driver -driver-print-jobs -target x86_64-unknown-windows-msvc -Ffoo -Fsystem car -F cdr -framework bar -Lbaz -lboo -Xlinker -undefined %s 2>&1 > %t.windows.txt
 // RUN: %FileCheck -check-prefix WINDOWS-x86_64 %s < %t.windows.txt
 
+// RUN: %swiftc_driver -driver-print-jobs -target amd64-unknown-openbsd -Ffoo -Fsystem car -F cdr -framework bar -Lbaz -lboo -Xlinker -undefined %s 2>&1 > %t.openbsd.txt
+// RUN: %FileCheck -check-prefix OPENBSD-amd64 %s < %t.openbsd.txt
+
 // RUN: %swiftc_driver -driver-print-jobs -emit-library -target x86_64-unknown-linux-gnu %s -Lbar -o dynlib.out 2>&1 > %t.linux.dynlib.txt
 // RUN: %FileCheck -check-prefix LINUX_DYNLIB-x86_64 %s < %t.linux.dynlib.txt
 
@@ -264,6 +267,22 @@
 // WINDOWS-x86_64-DAG: -Xlinker -undefined
 // WINDOWS-x86_64: -o linker
 
+// OPENBSD-amd64: swift
+// OPENBSD-amd64: -o [[OBJECTFILE:.*]]
+
+// OPENBSD-amd64: clang
+// OPENBSD-amd64-DAG: -fuse-ld=lld
+// OPENBSD-amd64-DAG: [[OBJECTFILE]]
+// OPENBSD-amd64-DAG: -lswiftCore
+// OPENBSD-amd64-DAG: -L [[STDLIB_PATH:[^ ]+(/|\\\\)lib(/|\\\\)swift(/|\\\\)]]
+// OPENBSD-amd64-DAG: -Xlinker -rpath -Xlinker [[STDLIB_PATH]]
+// OPENBSD-amd64-DAG: -F foo -iframework car -F cdr
+// OPENBSD-amd64-DAG: -framework bar
+// OPENBSD-amd64-DAG: -L baz
+// OPENBSD-amd64-DAG: -lboo
+// OPENBSD-amd64-DAG: -Xlinker -undefined
+// OPENBSD-amd64: -o linker
+
 
 // COMPLEX: {{(bin/)?}}ld{{"? }}
 // COMPLEX-DAG: -dylib

test/Parse/ConditionalCompilation/basicParseErrors.swift

@@ -78,6 +78,7 @@ struct S {
 // expected-note@-2{{did you mean 'FreeBSD'?}} {{8-15=FreeBSD}}
 // expected-note@-3{{did you mean 'Android'?}} {{8-15=Android}}
 // expected-note@-4{{did you mean 'OSX'?}} {{8-15=OSX}}
+// expected-note@-5{{did you mean 'OpenBSD'?}} {{8-15=OpenBSD}}
 #endif
 
 #if arch(leg) // expected-warning {{unknown architecture for build configuration 'arch'}} expected-note{{did you mean 'arm'?}} {{10-13=arm}}