Invert ArchSpec<->Platform dependency

Summary:
ArchSpec::SetTriple was taking a Platform as an argument, and used it to
fill in missing pieces of the specified triple. I invert the dependency
by moving this code to other classes. For this purpose, I've created
three new functions.
- HostInfo::GetAugmentedArchSpec: fills in the triple using the host
  platform (this used to be implemented by passing a null platform
  pointer). By putting this code in the Host module, we can provide a
  way to anyone who does not have a platform instance (lldb-server) an
  easy way to get Host data.
- Platform::GetAugmentedArchSpec: if you have a platform instance, you
  can call this to let it fill in the triple.
- static Platform::GetAugmentedArchSpec: implements the "if platform ==
  0 then use_host() else use_platform()" part.

Reviewers: zturner, jingham, clayborg

Subscribers: mgorny, javed.absar, lldb-commits

Differential Revision: https://reviews.llvm.org/D39387

llvm-svn: 316987

1 files changed, 31 insertions, 0 deletions

diff --git a/lldb/source/Target/Platform.cpp b/lldb/source/Target/Platform.cpp
index ab09517b633..60aa0079060 100644
--- a/lldb/source/Target/Platform.cpp
+++ b/lldb/source/Target/Platform.cpp
@@ -356,6 +356,12 @@ PlatformSP Platform::Create(const ArchSpec &arch, ArchSpec *platform_arch_ptr,
   return platform_sp;
 }
 
+ArchSpec Platform::GetAugmentedArchSpec(Platform *platform, llvm::StringRef triple) {
+  if (platform)
+    return platform->GetAugmentedArchSpec(triple);
+  return HostInfo::GetAugmentedArchSpec(triple);
+}
+
 //------------------------------------------------------------------
 /// Default Constructor
 //------------------------------------------------------------------
@@ -963,6 +969,31 @@ const ArchSpec &Platform::GetSystemArchitecture() {
   return m_system_arch;
 }
 
+ArchSpec Platform::GetAugmentedArchSpec(llvm::StringRef triple) {
+  if (triple.empty())
+    return ArchSpec();
+  llvm::Triple normalized_triple(llvm::Triple::normalize(triple));
+  if (!ArchSpec::ContainsOnlyArch(normalized_triple))
+    return ArchSpec(triple);
+
+  ArchSpec compatible_arch;
+  ArchSpec raw_arch(triple);
+  if (!IsCompatibleArchitecture(raw_arch, false, &compatible_arch))
+    return raw_arch;
+
+  if (!compatible_arch.IsValid())
+    return ArchSpec(normalized_triple);
+
+  const llvm::Triple &compatible_triple = compatible_arch.GetTriple();
+  if (normalized_triple.getVendorName().empty())
+    normalized_triple.setVendor(compatible_triple.getVendor());
+  if (normalized_triple.getOSName().empty())
+    normalized_triple.setOS(compatible_triple.getOS());
+  if (normalized_triple.getEnvironmentName().empty())
+    normalized_triple.setEnvironment(compatible_triple.getEnvironment());
+  return ArchSpec(normalized_triple);
+}
+
 Status Platform::ConnectRemote(Args &args) {
   Status error;
   if (IsHost())