[LLDB][MIPS] Provide CPU string to compiler for appropriate code generation for MIPS

BhushanIMG · BhushanIMG · commit 3592a6ec6bdc · 2016-02-18T11:53:28.000Z
SUMMARY: This patch implements ArchSpec::GetClangTargetCPU() that provides string representing current architecture as a target CPU. This string is then passed to tools like clang so that they generate correct code for that target. Reviewers: clayborg, zturner Subscribers: mohit.bhakkad, sagar, jaydeep, lldb-commits Differential Revision: http://reviews.llvm.org/D17022 llvm-svn: 261206
diff --git a/lldb/include/lldb/Core/ArchSpec.h b/lldb/include/lldb/Core/ArchSpec.h
@@ -287,6 +287,16 @@ class ArchSpec
     const char *
     GetArchitectureName () const;
 
+    //------------------------------------------------------------------
+    /// Returns a string representing current architecture as a target CPU
+    /// for tools like compiler, disassembler etc.
+    ///
+    /// @return A string representing target CPU for the current
+    ///         architecture.
+    //------------------------------------------------------------------
+    std::string
+    GetClangTargetCPU ();
+
     //------------------------------------------------------------------
     /// Clears the object state.
     ///
diff --git a/lldb/source/Core/ArchSpec.cpp b/lldb/source/Core/ArchSpec.cpp
@@ -511,6 +511,56 @@ ArchSpec::GetArchitectureName () const
     return "unknown";
 }
 
+std::string
+ArchSpec::GetClangTargetCPU ()
+{
+    std::string cpu;
+    const llvm::Triple::ArchType machine = GetMachine();
+
+    if (machine == llvm::Triple::mips ||
+        machine == llvm::Triple::mipsel ||
+        machine == llvm::Triple::mips64 ||
+        machine == llvm::Triple::mips64el)
+    {
+        switch (m_core)
+        {
+        case ArchSpec::eCore_mips32:
+        case ArchSpec::eCore_mips32el:
+            cpu = "mips32"; break;
+        case ArchSpec::eCore_mips32r2:
+        case ArchSpec::eCore_mips32r2el:
+            cpu = "mips32r2"; break;
+        case ArchSpec::eCore_mips32r3:
+        case ArchSpec::eCore_mips32r3el:
+            cpu = "mips32r3"; break;
+        case ArchSpec::eCore_mips32r5:
+        case ArchSpec::eCore_mips32r5el:
+            cpu = "mips32r5"; break;
+        case ArchSpec::eCore_mips32r6:
+        case ArchSpec::eCore_mips32r6el:
+            cpu = "mips32r6"; break;
+        case ArchSpec::eCore_mips64:
+        case ArchSpec::eCore_mips64el:
+            cpu = "mips64"; break;
+        case ArchSpec::eCore_mips64r2:
+        case ArchSpec::eCore_mips64r2el:
+            cpu = "mips64r2"; break;
+        case ArchSpec::eCore_mips64r3:
+        case ArchSpec::eCore_mips64r3el:
+            cpu = "mips64r3"; break;
+        case ArchSpec::eCore_mips64r5:
+        case ArchSpec::eCore_mips64r5el:
+            cpu = "mips64r5"; break;
+        case ArchSpec::eCore_mips64r6:
+        case ArchSpec::eCore_mips64r6el:
+            cpu = "mips64r6"; break;
+        default:
+            break;
+        }
+    }
+    return cpu;
+}
+
 uint32_t
 ArchSpec::GetMachOCPUType () const
 {
diff --git a/lldb/source/Plugins/ExpressionParser/Clang/ClangExpressionParser.cpp b/lldb/source/Plugins/ExpressionParser/Clang/ClangExpressionParser.cpp
@@ -179,6 +179,12 @@ ClangExpressionParser::ClangExpressionParser (ExecutionContextScope *exe_scope,
     if (exe_scope)
         target_sp = exe_scope->CalculateTarget();
 
+    ArchSpec target_arch;
+    if (target_sp)
+        target_arch = target_sp->GetArchitecture();
+
+    const auto target_machine = target_arch.GetMachine();
+
     // If the expression is being evaluated in the context of an existing
     // stack frame, we introspect to see if the language runtime is available.
     auto frame = exe_scope->CalculateStackFrame();
@@ -197,9 +203,9 @@ ClangExpressionParser::ClangExpressionParser (ExecutionContextScope *exe_scope,
 
     // 2. Configure the compiler with a set of default options that are appropriate
     // for most situations.
-    if (target_sp && target_sp->GetArchitecture().IsValid())
+    if (target_sp && target_arch.IsValid())
     {
-        std::string triple = target_sp->GetArchitecture().GetTriple().str();
+        std::string triple = target_arch.GetTriple().str();
         m_compiler->getTargetOpts().Triple = triple;
         if (log)
             log->Printf("Using %s as the target triple", m_compiler->getTargetOpts().Triple.c_str());
@@ -224,13 +230,17 @@ ClangExpressionParser::ClangExpressionParser (ExecutionContextScope *exe_scope,
         m_compiler->getTargetOpts().ABI = "apcs-gnu";
     }
     // Supported subsets of x86
-    if (target_sp->GetArchitecture().GetMachine() == llvm::Triple::x86 ||
-        target_sp->GetArchitecture().GetMachine() == llvm::Triple::x86_64)
+    if (target_machine == llvm::Triple::x86 ||
+        target_machine == llvm::Triple::x86_64)
     {
         m_compiler->getTargetOpts().Features.push_back("+sse");
         m_compiler->getTargetOpts().Features.push_back("+sse2");
     }
 
+    // Set the target CPU to generate code for.
+    // This will be empty for any CPU that doesn't really need to make a special CPU string.
+    m_compiler->getTargetOpts().CPU = target_arch.GetClangTargetCPU();
+
     // 3. Now allow the runtime to provide custom configuration options for the target.
     // In this case, a specialized language runtime is available and we can query it for extra options.
     // For 99% of use cases, this will not be needed and should be provided when basic platform detection is not enough.
