ABI Plugin for MIPS32

[bhushan]

Summary

This patch implements ABI plugin for MIPS32.

[clayborg]

lgtm

cmake/LLDBDependencies.cmake

set( LLDB_USED_LIBS
   lldbPluginABIMacOSX_arm64
   lldbPluginABIMacOSX_i386
   lldbPluginABISysV_arm
   lldbPluginABISysV_arm64
   lldbPluginABISysV_x86_64
   lldbPluginABISysV_hexagon
   lldbPluginABISysV_ppc
   lldbPluginABISysV_ppc64
+  lldbPluginABISysV_mips
   lldbPluginInstructionARM
   lldbPluginInstructionARM64
   lldbPluginInstructionMIPS
   lldbPluginInstructionMIPS64
   lldbPluginObjectFilePECOFF
   lldbPluginOSPython
   lldbPluginMemoryHistoryASan
   lldbPluginInstrumentationRuntimeAddressSanitizer

lib/Makefile

USEDLIBS = lldbAPI.a \
   lldbInterpreter.a \
   lldbPluginABIMacOSX_arm.a \
   lldbPluginABIMacOSX_arm64.a \
   lldbPluginABIMacOSX_i386.a \
   lldbPluginABISysV_arm.a \
   lldbPluginABISysV_arm64.a \
   lldbPluginABISysV_ppc.a \
   lldbPluginABISysV_ppc64.a \
+  lldbPluginABISysV_mips.a \
   lldbPluginABISysV_x86_64.a \
   lldbPluginABISysV_hexagon.a \
   lldbPluginDisassemblerLLVM.a \
   lldbPluginDynamicLoaderStatic.a \
   lldbPluginDynamicLoaderPOSIX.a \
   lldbPluginDynamicLoaderHexagon.a \
   lldbPluginDynamicLoaderMacOSX.a \
   lldbPluginEmulateInstructionARM.a \

source/API/SystemInitializerFull.cpp

 #include "Plugins/ABI/MacOSX-i386/ABIMacOSX_i386.h"
 #include "Plugins/ABI/MacOSX-arm/ABIMacOSX_arm.h"
 #include "Plugins/ABI/MacOSX-arm64/ABIMacOSX_arm64.h"
 #include "Plugins/ABI/SysV-arm/ABISysV_arm.h"
 #include "Plugins/ABI/SysV-arm64/ABISysV_arm64.h"
 #include "Plugins/ABI/SysV-x86_64/ABISysV_x86_64.h"
 #include "Plugins/ABI/SysV-ppc/ABISysV_ppc.h"
 #include "Plugins/ABI/SysV-ppc64/ABISysV_ppc64.h"
+#include "Plugins/ABI/SysV-mips/ABISysV_mips.h"
 #include "Plugins/Disassembler/llvm/DisassemblerLLVMC.h"
 #include "Plugins/DynamicLoader/Static/DynamicLoaderStatic.h"
 #include "Plugins/Instruction/ARM64/EmulateInstructionARM64.h"
 #include "Plugins/InstrumentationRuntime/AddressSanitizer/AddressSanitizerRuntime.h"
 #include "Plugins/JITLoader/GDB/JITLoaderGDB.h"
 #include "Plugins/LanguageRuntime/CPlusPlus/ItaniumABI/ItaniumABILanguageRuntime.h"
 #include "Plugins/LanguageRuntime/ObjC/AppleObjCRuntime/AppleObjCRuntimeV1.h"
 #include "Plugins/LanguageRuntime/ObjC/AppleObjCRuntime/AppleObjCRuntimeV2.h"
SystemInitializerFull::Initialize()
     ABIMacOSX_i386::Initialize();
     ABIMacOSX_arm::Initialize();
     ABIMacOSX_arm64::Initialize();
     ABISysV_arm::Initialize();
     ABISysV_arm64::Initialize();
     ABISysV_x86_64::Initialize();
     ABISysV_ppc::Initialize();
     ABISysV_ppc64::Initialize();
+    ABISysV_mips::Initialize();
     DisassemblerLLVMC::Initialize();
 
     JITLoaderGDB::Initialize();
     ProcessElfCore::Initialize();
     MemoryHistoryASan::Initialize();
     AddressSanitizerRuntime::Initialize();
 
     SymbolVendorELF::Initialize();
SystemInitializerFull::Terminate()
     ABIMacOSX_i386::Terminate();
     ABIMacOSX_arm::Terminate();
     ABIMacOSX_arm64::Terminate();
     ABISysV_arm::Terminate();
     ABISysV_arm64::Terminate();
     ABISysV_x86_64::Terminate();
     ABISysV_ppc::Terminate();
     ABISysV_ppc64::Terminate();
+    ABISysV_mips::Terminate();
     DisassemblerLLVMC::Terminate();
 
     JITLoaderGDB::Terminate();
     ProcessElfCore::Terminate();
     MemoryHistoryASan::Terminate();
     AddressSanitizerRuntime::Terminate();
     SymbolVendorELF::Terminate();
     SymbolFileDWARF::Terminate();

source/Plugins/ABI/CMakeLists.txt

 add_subdirectory(SysV-arm)
 add_subdirectory(SysV-arm64)
 add_subdirectory(SysV-hexagon)
 add_subdirectory(SysV-ppc)
 add_subdirectory(SysV-ppc64)
+add_subdirectory(SysV-mips)
 add_subdirectory(SysV-x86_64)
 add_subdirectory(MacOSX-i386)
 add_subdirectory(MacOSX-arm)
 add_subdirectory(MacOSX-arm64)

source/Plugins/ABI/SysV-mips/ABISysV_mips.h

+//===-- ABISysV_mips.h ----------------------------------------*- C++ -*-===//
+//
+//                     The LLVM Compiler Infrastructure
+//
+// This file is distributed under the University of Illinois Open Source
+// License. See LICENSE.TXT for details.
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef liblldb_ABISysV_mips_h_
+#define liblldb_ABISysV_mips_h_
+
+// C Includes
+// C++ Includes
+// Other libraries and framework includes
+// Project includes
+#include "lldb/lldb-private.h"
+#include "lldb/Target/ABI.h"
+
+class ABISysV_mips :
+    public lldb_private::ABI
+{
+public:
+
+    ~ABISysV_mips()
+    {
+    }
+
+    virtual size_t
+    GetRedZoneSize () const;
+
+    virtual bool
+    PrepareTrivialCall (lldb_private::Thread &thread, 
+                        lldb::addr_t sp,
+                        lldb::addr_t functionAddress,
+                        lldb::addr_t returnAddress, 
+                        llvm::ArrayRef<lldb::addr_t> args) const;
+
+    virtual bool
+    GetArgumentValues (lldb_private::Thread &thread,
+                       lldb_private::ValueList &values) const;
+
+    virtual lldb_private::Error
+    SetReturnValueObject(lldb::StackFrameSP &frame_sp, lldb::ValueObjectSP &new_value);
+
+protected:
+    lldb::ValueObjectSP
+    GetReturnValueObjectSimple (lldb_private::Thread &thread,
+                                lldb_private::ClangASTType &ast_type) const;
+    
+public:    
+    virtual lldb::ValueObjectSP
+    GetReturnValueObjectImpl (lldb_private::Thread &thread,
+                          lldb_private::ClangASTType &type) const;
+
+    virtual bool
+    CreateFunctionEntryUnwindPlan (lldb_private::UnwindPlan &unwind_plan);
+
+    virtual bool
+    CreateDefaultUnwindPlan (lldb_private::UnwindPlan &unwind_plan);
+
+    virtual bool
+    RegisterIsVolatile (const lldb_private::RegisterInfo *reg_info);
+
+    virtual bool
+    CallFrameAddressIsValid (lldb::addr_t cfa)
+    {
+        // Make sure the stack call frame addresses are 8 byte aligned
+        if (cfa & (8ull - 1ull))
+            return false;   // Not 8 byte aligned
+        if (cfa == 0)
+            return false;   // Zero is not a valid stack address
+        return true;
+    }
+
+    virtual bool
+    CodeAddressIsValid (lldb::addr_t pc)//must- check
+    {
+       if (pc & (4ull - 1ull))
+           return false;   // Not 4 byte aligned
+        
+        // Anything else if fair game..
+        return true;
+    }
+
+    virtual const lldb_private::RegisterInfo *
+    GetRegisterInfoArray (uint32_t &count);
+    //------------------------------------------------------------------
+    // Static Functions
+    //------------------------------------------------------------------
+    static void
+    Initialize();
+
+    static void
+    Terminate();
+
+    static lldb::ABISP
+    CreateInstance (const lldb_private::ArchSpec &arch);
+
+    static lldb_private::ConstString
+    GetPluginNameStatic();
+    
+    //------------------------------------------------------------------
+    // PluginInterface protocol
+    //------------------------------------------------------------------
+    virtual lldb_private::ConstString
+    GetPluginName();
+
+    virtual uint32_t
+    GetPluginVersion();
+
+protected:
+    void
+    CreateRegisterMapIfNeeded ();
+
+    bool
+    RegisterIsCalleeSaved (const lldb_private::RegisterInfo *reg_info);
+
+private:
+    ABISysV_mips() : lldb_private::ABI() { } // Call CreateInstance instead.
+};
+
+#endif  // liblldb_ABI_h_

source/Plugins/ABI/SysV-mips/ABISysV_mips.cpp

+//===-- ABISysV_mips.cpp ----------------------------------------*- C++ -*-===//
+//
+//                     The LLVM Compiler Infrastructure
+//
+// This file is distributed under the University of Illinois Open Source
+// License. See LICENSE.TXT for details.
+//
+//===----------------------------------------------------------------------===//
+
+#include "ABISysV_mips.h"
+
+#include "lldb/Core/ConstString.h"
+#include "lldb/Core/DataExtractor.h"
+#include "lldb/Core/Error.h"
+#include "lldb/Core/Log.h"
+#include "lldb/Core/Module.h"
+#include "lldb/Core/PluginManager.h"
+#include "lldb/Core/RegisterValue.h"
+#include "lldb/Core/Value.h"
+#include "lldb/Core/ValueObjectConstResult.h"
+#include "lldb/Core/ValueObjectRegister.h"
+#include "lldb/Core/ValueObjectMemory.h"
+#include "lldb/Symbol/ClangASTContext.h"
+#include "lldb/Symbol/UnwindPlan.h"
+#include "lldb/Target/Target.h"
+#include "lldb/Target/Process.h"
+#include "lldb/Target/RegisterContext.h"
+#include "lldb/Target/StackFrame.h"
+#include "lldb/Target/Thread.h"
+
+#include "llvm/ADT/STLExtras.h"
+#include "llvm/ADT/Triple.h"
+
+using namespace lldb;
+using namespace lldb_private;
+
+enum gcc_dwarf_regnums
+{
+    gcc_dwarf_r0 = 0,
+    gcc_dwarf_r1,
+    gcc_dwarf_r2,
+    gcc_dwarf_r3,
+    gcc_dwarf_r4,
+    gcc_dwarf_r5,
+    gcc_dwarf_r6,
+    gcc_dwarf_r7,
+    gcc_dwarf_r8,
+    gcc_dwarf_r9,
+    gcc_dwarf_r10,
+    gcc_dwarf_r11,
+    gcc_dwarf_r12,
+    gcc_dwarf_r13,
+    gcc_dwarf_r14,
+    gcc_dwarf_r15,
+    gcc_dwarf_r16,
+    gcc_dwarf_r17,
+    gcc_dwarf_r18,
+    gcc_dwarf_r19,
+    gcc_dwarf_r20,
+    gcc_dwarf_r21,
+    gcc_dwarf_r22,
+    gcc_dwarf_r23,
+    gcc_dwarf_r24,
+    gcc_dwarf_r25,
+    gcc_dwarf_r26,
+    gcc_dwarf_r27,
+    gcc_dwarf_r28,
+    gcc_dwarf_r29,
+    gcc_dwarf_r30,
+    gcc_dwarf_r31,
+    gcc_dwarf_sr,
+    gcc_dwarf_lo,
+    gcc_dwarf_hi,
+    gcc_dwarf_bad,
+    gcc_dwarf_cause,
+    gcc_dwarf_pc
+};
+
+enum gdb_regnums
+{
+    gdb_r0 = 0,
+    gdb_r1,
+    gdb_r2,
+    gdb_r3,
+    gdb_r4,
+    gdb_r5,
+    gdb_r6,
+    gdb_r7,
+    gdb_r8,
+    gdb_r9,
+    gdb_r10,
+    gdb_r11,
+    gdb_r12,
+    gdb_r13,
+    gdb_r14,
+    gdb_r15,
+    gdb_r16,
+    gdb_r17,
+    gdb_r18,
+    gdb_r19,
+    gdb_r20,
+    gdb_r21,
+    gdb_r22,
+    gdb_r23,
+    gdb_r24,
+    gdb_r25,
+    gdb_r26,
+    gdb_r27,
+    gdb_r28,
+    gdb_r29,
+    gdb_r30,
+    gdb_r31,
+    gdb_sr,
+    gdb_lo,
+    gdb_hi,
+    gdb_bad,
+    gdb_cause,
+    gdb_pc
+};
+
+static const RegisterInfo
+g_register_infos[] =
+{
+   //  NAME      ALT    SZ OFF ENCODING        FORMAT        COMPILER                DWARF                 GENERIC                   GDB           LLDB NATIVE       VALUE REGS  INVALIDATE REGS
+  //  ========  ======  == === =============  =================== ============ ===================== ==================== =================     ====================== ========== ===============
+    { "r0"    , "zero", 4,  0, eEncodingUint, eFormatHex,  { gcc_dwarf_r0,      gcc_dwarf_r0,           LLDB_INVALID_REGNUM,        gdb_r0,     LLDB_INVALID_REGNUM },  NULL,      NULL},
+    { "r1"    , "AT",   4,  0, eEncodingUint, eFormatHex,  { gcc_dwarf_r1,      gcc_dwarf_r1,           LLDB_INVALID_REGNUM,        gdb_r1,     LLDB_INVALID_REGNUM },  NULL,      NULL},
+    { "r2"    , "v0",   4,  0, eEncodingUint, eFormatHex,  { gcc_dwarf_r2,      gcc_dwarf_r2,           LLDB_INVALID_REGNUM,        gdb_r2,     LLDB_INVALID_REGNUM },  NULL,      NULL},
+    { "r3"    , "v1",   4,  0, eEncodingUint, eFormatHex,  { gcc_dwarf_r3,      gcc_dwarf_r3,           LLDB_INVALID_REGNUM,        gdb_r3,     LLDB_INVALID_REGNUM },  NULL,      NULL},
+    { "r4"    , "arg1", 4,  0, eEncodingUint, eFormatHex,  { gcc_dwarf_r4,      gcc_dwarf_r4,           LLDB_REGNUM_GENERIC_ARG1,   gdb_r4,     LLDB_INVALID_REGNUM },  NULL,      NULL},
+    { "r5"    , "arg2", 4,  0, eEncodingUint, eFormatHex,  { gcc_dwarf_r5,      gcc_dwarf_r5,           LLDB_REGNUM_GENERIC_ARG2,   gdb_r5,     LLDB_INVALID_REGNUM },  NULL,      NULL},
+    { "r6"    , "arg3", 4,  0, eEncodingUint, eFormatHex,  { gcc_dwarf_r6,      gcc_dwarf_r6,           LLDB_REGNUM_GENERIC_ARG3,   gdb_r6,     LLDB_INVALID_REGNUM },  NULL,      NULL},
+    { "r7"    , "arg4", 4,  0, eEncodingUint, eFormatHex,  { gcc_dwarf_r7,      gcc_dwarf_r7,           LLDB_REGNUM_GENERIC_ARG4,   gdb_r7,     LLDB_INVALID_REGNUM },  NULL,      NULL},
+    { "r8"    , "arg5", 4,  0, eEncodingUint, eFormatHex,  { gcc_dwarf_r8,      gcc_dwarf_r8,           LLDB_INVALID_REGNUM,        gdb_r8,     LLDB_INVALID_REGNUM },  NULL,      NULL},
+    { "r9"    , "arg6", 4,  0, eEncodingUint, eFormatHex,  { gcc_dwarf_r9,      gcc_dwarf_r9,           LLDB_INVALID_REGNUM,        gdb_r9,     LLDB_INVALID_REGNUM },  NULL,      NULL},
+    { "r10"   , "arg7", 4,  0, eEncodingUint, eFormatHex,  { gcc_dwarf_r10,     gcc_dwarf_r10,          LLDB_INVALID_REGNUM,        gdb_r10,    LLDB_INVALID_REGNUM },  NULL,      NULL},
+    { "r11"   , "arg8", 4,  0, eEncodingUint, eFormatHex,  { gcc_dwarf_r11,     gcc_dwarf_r11,          LLDB_INVALID_REGNUM,        gdb_r11,    LLDB_INVALID_REGNUM },  NULL,      NULL},
+    { "r12"   , NULL,   4,  0, eEncodingUint, eFormatHex,  { gcc_dwarf_r12,     gcc_dwarf_r12,          LLDB_INVALID_REGNUM,        gdb_r12,    LLDB_INVALID_REGNUM },  NULL,      NULL},
+    { "r13"   , NULL,   4,  0, eEncodingUint, eFormatHex,  { gcc_dwarf_r13,     gcc_dwarf_r13,          LLDB_INVALID_REGNUM,        gdb_r13,    LLDB_INVALID_REGNUM },  NULL,      NULL},
+    { "r14"   , NULL,   4,  0, eEncodingUint, eFormatHex,  { gcc_dwarf_r14,     gcc_dwarf_r14,          LLDB_INVALID_REGNUM,        gdb_r14,    LLDB_INVALID_REGNUM },  NULL,      NULL},
+    { "r15"   , NULL,   4,  0, eEncodingUint, eFormatHex,  { gcc_dwarf_r15,     gcc_dwarf_r15,          LLDB_INVALID_REGNUM,        gdb_r15,    LLDB_INVALID_REGNUM },  NULL,      NULL},
+    { "r16"   , NULL,   4,  0, eEncodingUint, eFormatHex,  { gcc_dwarf_r16,     gcc_dwarf_r16,          LLDB_INVALID_REGNUM,        gdb_r16,    LLDB_INVALID_REGNUM },  NULL,      NULL},
+    { "r17"   , NULL,   4,  0, eEncodingUint, eFormatHex,  { gcc_dwarf_r17,     gcc_dwarf_r17,          LLDB_INVALID_REGNUM,        gdb_r17,    LLDB_INVALID_REGNUM },  NULL,      NULL},
+    { "r18"   , NULL,   4,  0, eEncodingUint, eFormatHex,  { gcc_dwarf_r18,     gcc_dwarf_r18,          LLDB_INVALID_REGNUM,        gdb_r18,    LLDB_INVALID_REGNUM },  NULL,      NULL},
+    { "r19"   , NULL,   4,  0, eEncodingUint, eFormatHex,  { gcc_dwarf_r19,     gcc_dwarf_r19,          LLDB_INVALID_REGNUM,        gdb_r19,    LLDB_INVALID_REGNUM },  NULL,      NULL},
+    { "r20"   , NULL,   4,  0, eEncodingUint, eFormatHex,  { gcc_dwarf_r20,     gcc_dwarf_r20,          LLDB_INVALID_REGNUM,        gdb_r20,    LLDB_INVALID_REGNUM },  NULL,      NULL},
+    { "r21"   , NULL,   4,  0, eEncodingUint, eFormatHex,  { gcc_dwarf_r21,     gcc_dwarf_r21,          LLDB_INVALID_REGNUM,        gdb_r21,    LLDB_INVALID_REGNUM },  NULL,      NULL},
+    { "r22"   , NULL,   4,  0, eEncodingUint, eFormatHex,  { gcc_dwarf_r22,     gcc_dwarf_r22,          LLDB_INVALID_REGNUM,        gdb_r22,    LLDB_INVALID_REGNUM },  NULL,      NULL},
+    { "r23"   , NULL,   4,  0, eEncodingUint, eFormatHex,  { gcc_dwarf_r23,     gcc_dwarf_r23,          LLDB_INVALID_REGNUM,        gdb_r23,    LLDB_INVALID_REGNUM },  NULL,      NULL},
+    { "r24"   , NULL,   4,  0, eEncodingUint, eFormatHex,  { gcc_dwarf_r24,     gcc_dwarf_r24,          LLDB_INVALID_REGNUM,        gdb_r24,    LLDB_INVALID_REGNUM },  NULL,      NULL},
+    { "r25"   , NULL,   4,  0, eEncodingUint, eFormatHex,  { gcc_dwarf_r25,     gcc_dwarf_r25,          LLDB_INVALID_REGNUM,        gdb_r25,    LLDB_INVALID_REGNUM },  NULL,      NULL},
+    { "r26"   , NULL,   4,  0, eEncodingUint, eFormatHex,  { gcc_dwarf_r26,     gcc_dwarf_r26,          LLDB_INVALID_REGNUM,        gdb_r26,    LLDB_INVALID_REGNUM },  NULL,      NULL},
+    { "r27"   , NULL,   4,  0, eEncodingUint, eFormatHex,  { gcc_dwarf_r27,     gcc_dwarf_r27,          LLDB_INVALID_REGNUM,        gdb_r27,    LLDB_INVALID_REGNUM },  NULL,      NULL},
+    { "r28"   , "gp",   4,  0, eEncodingUint, eFormatHex,  { gcc_dwarf_r28,     gcc_dwarf_r28,          LLDB_INVALID_REGNUM,        gdb_r28,    LLDB_INVALID_REGNUM },  NULL,      NULL},
+    { "r29"   , "sp",   4,  0, eEncodingUint, eFormatHex,  { gcc_dwarf_r29,     gcc_dwarf_r29,          LLDB_REGNUM_GENERIC_SP,     gdb_r29,    LLDB_INVALID_REGNUM },  NULL,      NULL},
+    { "r30"   , "fp",   4,  0, eEncodingUint, eFormatHex,  { gcc_dwarf_r30,     gcc_dwarf_r30,          LLDB_REGNUM_GENERIC_FP,     gdb_r30,    LLDB_INVALID_REGNUM },  NULL,      NULL},
+    { "r31"   , "ra",   4,  0, eEncodingUint, eFormatHex,  { gcc_dwarf_r31,     gcc_dwarf_r31,          LLDB_REGNUM_GENERIC_RA,     gdb_r31,    LLDB_INVALID_REGNUM },  NULL,      NULL},
+    { "sr"    , NULL,   4,  0, eEncodingUint, eFormatHex,  { gcc_dwarf_sr,      gcc_dwarf_sr,           LLDB_REGNUM_GENERIC_FLAGS,  gdb_sr,     LLDB_INVALID_REGNUM },  NULL,      NULL},
+    { "lo"    , NULL,   4,  0, eEncodingUint, eFormatHex,  { gcc_dwarf_lo,      gcc_dwarf_lo,           LLDB_INVALID_REGNUM,        gdb_lo,     LLDB_INVALID_REGNUM },  NULL,      NULL},
+    { "hi"    , NULL,   4,  0, eEncodingUint, eFormatHex,  { gcc_dwarf_hi,      gcc_dwarf_hi,           LLDB_INVALID_REGNUM,        gdb_hi,     LLDB_INVALID_REGNUM },  NULL,      NULL},
+    { "bad"   , NULL,   4,  0, eEncodingUint, eFormatHex,  { gcc_dwarf_bad,     gcc_dwarf_bad,          LLDB_INVALID_REGNUM,        gdb_bad,    LLDB_INVALID_REGNUM },  NULL,      NULL},
+    { "cause" , NULL,   4,  0, eEncodingUint, eFormatHex,  { gcc_dwarf_cause,   gcc_dwarf_cause,        LLDB_INVALID_REGNUM,        gdb_cause,  LLDB_INVALID_REGNUM },  NULL,      NULL},
+    { "pc"    , NULL,   4,  0, eEncodingUint, eFormatHex,  { gcc_dwarf_pc,      gcc_dwarf_pc,           LLDB_REGNUM_GENERIC_PC,     gdb_pc,     LLDB_INVALID_REGNUM },  NULL,      NULL},
+};
+
+static const uint32_t k_num_register_infos = llvm::array_lengthof(g_register_infos);
+
+const lldb_private::RegisterInfo *
+ABISysV_mips::GetRegisterInfoArray (uint32_t &count)
+{
+    count = k_num_register_infos;
+    return g_register_infos;
+}
+
+size_t
+ABISysV_mips::GetRedZoneSize () const
+{
+    return 0;
+}
+
+//------------------------------------------------------------------
+// Static Functions
+//------------------------------------------------------------------
+ABISP
+ABISysV_mips::CreateInstance (const ArchSpec &arch)
+{
+    static ABISP g_abi_sp;
+    const llvm::Triple::ArchType arch_type = arch.GetTriple().getArch();
+    if ((arch_type == llvm::Triple::mips) ||
+        (arch_type == llvm::Triple::mipsel))
+    {
+        if (!g_abi_sp)
+            g_abi_sp.reset (new ABISysV_mips);
+        return g_abi_sp;
+    }
+    return ABISP();
+}
+
+bool
+ABISysV_mips::PrepareTrivialCall (Thread &thread,
+                                  addr_t sp,
+                                  addr_t func_addr,
+                                  addr_t return_addr,
+                                  llvm::ArrayRef<addr_t> args) const
+{
+    Log *log(lldb_private::GetLogIfAllCategoriesSet (LIBLLDB_LOG_EXPRESSIONS));
+
+    if (log)
+    {
+        StreamString s;
+        s.Printf("ABISysV_mips::PrepareTrivialCall (tid = 0x%" PRIx64 ", sp = 0x%" PRIx64 ", func_addr = 0x%" PRIx64 ", return_addr = 0x%" PRIx64,
+                    thread.GetID(),
+                    (uint64_t)sp,
+                    (uint64_t)func_addr,
+                    (uint64_t)return_addr);
+
+        for (size_t i = 0; i < args.size(); ++i)
+            s.Printf (", arg%zd = 0x%" PRIx64, i + 1, args[i]);
+        s.PutCString (")");
+        log->PutCString(s.GetString().c_str());
+    }
+
+    RegisterContext *reg_ctx = thread.GetRegisterContext().get();
+    if (!reg_ctx)
+        return false;
+
+    const RegisterInfo *reg_info = NULL;
+
+    RegisterValue reg_value;
+
+    // Argument registers
+    const char *reg_names[] = { "r4", "r5", "r6", "r7" };
+
+    llvm::ArrayRef<addr_t>::iterator ai = args.begin(), ae = args.end();
+
+    // Write arguments to registers
+    for (size_t i = 0; i < llvm::array_lengthof(reg_names); ++i)
+    {
+        if (ai == ae)
+            break;
+
+        reg_info = reg_ctx->GetRegisterInfo(eRegisterKindGeneric, LLDB_REGNUM_GENERIC_ARG1 + i);
+        if (log)
+            log->Printf("About to write arg%zd (0x%" PRIx64 ") into %s", i + 1, args[i], reg_info->name);
+
+        if (!reg_ctx->WriteRegisterFromUnsigned(reg_info, args[i]))
+            return false;
+
+        ++ai;
+    }
+
+    // If we have more than 4 arguments --Spill onto the stack
+    if (ai != ae)
+    {
+        // No of arguments to go on stack 
+        size_t num_stack_regs = args.size();
+
+        // Allocate needed space for args on the stack
+        sp -= (num_stack_regs * 4);
+
+        // Keep the stack 8 byte aligned
+        sp &= ~(8ull-1ull);
+
+        // just using arg1 to get the right size
+        const RegisterInfo *reg_info = reg_ctx->GetRegisterInfo(eRegisterKindGeneric, LLDB_REGNUM_GENERIC_ARG1);
+        
+        addr_t arg_pos = sp+16;
+        
+        size_t i = 4;
+        for (; ai != ae; ++ai)
+        {
+            reg_value.SetUInt32(*ai);
+            if (log)
+                log->Printf("About to write arg%zd (0x%" PRIx64 ") at  0x%" PRIx64 "", i+1, args[i], arg_pos);
+            
+            if (reg_ctx->WriteRegisterValueToMemory(reg_info, arg_pos, reg_info->byte_size, reg_value).Fail())
+                return false;
+            arg_pos += reg_info->byte_size;
+            i++;
+        }
+    }
+
+    Error error;
+    const RegisterInfo *pc_reg_info = reg_ctx->GetRegisterInfo (eRegisterKindGeneric, LLDB_REGNUM_GENERIC_PC);
+    const RegisterInfo *sp_reg_info = reg_ctx->GetRegisterInfo (eRegisterKindGeneric, LLDB_REGNUM_GENERIC_SP);
+    const RegisterInfo *ra_reg_info = reg_ctx->GetRegisterInfo (eRegisterKindGeneric, LLDB_REGNUM_GENERIC_RA);
+
+    if (log)
+    log->Printf("Writing SP: 0x%" PRIx64, (uint64_t)sp);
+
+    // Set "sp" to the requested value
+    if (!reg_ctx->WriteRegisterFromUnsigned (sp_reg_info, sp))
+        return false;
+
+    if (log)
+    log->Printf("Writing RA: 0x%" PRIx64, (uint64_t)return_addr);
+
+    // Set "ra" to the return address
+    if (!reg_ctx->WriteRegisterFromUnsigned (ra_reg_info, return_addr))
+        return false;
+
+    if (log)
+        log->Printf("Writing PC: 0x%" PRIx64, (uint64_t)func_addr);
+
+    // Set pc to the address of the called function.
+    if (!reg_ctx->WriteRegisterFromUnsigned (pc_reg_info, func_addr))
+        return false;
+
+    return true;
+}
+
+bool
+ABISysV_mips::GetArgumentValues (Thread &thread, ValueList &values) const
+{
+    return false;
+}
+
+Error
+ABISysV_mips::SetReturnValueObject(lldb::StackFrameSP &frame_sp, lldb::ValueObjectSP &new_value_sp)
+{
+    Error error;
+    if (!new_value_sp)
+    {
+        error.SetErrorString("Empty value object for return value.");
+        return error;
+    }
+
+    ClangASTType clang_type = new_value_sp->GetClangType();
+    if (!clang_type)
+    {
+        error.SetErrorString ("Null clang type for return value.");
+        return error;
+    }
+
+    Thread *thread = frame_sp->GetThread().get();
+
+    bool is_signed;
+    uint32_t count;
+    bool is_complex;
+
+    RegisterContext *reg_ctx = thread->GetRegisterContext().get();
+
+    bool set_it_simple = false;
+    if (clang_type.IsIntegerType (is_signed) || clang_type.IsPointerType())
+    {
+        DataExtractor data;
+        Error data_error;
+        size_t num_bytes = new_value_sp->GetData(data, data_error);
+        if (data_error.Fail())
+        {
+            error.SetErrorStringWithFormat("Couldn't convert return value to raw data: %s", data_error.AsCString());
+            return error;
+        }
+
+        lldb::offset_t offset = 0;
+        if (num_bytes <= 8)
+        {
+            const RegisterInfo *r2_info = reg_ctx->GetRegisterInfoByName("r2", 0);
+            if (num_bytes <= 4)
+            {
+                uint32_t raw_value = data.GetMaxU32(&offset, num_bytes);
+
+                if (reg_ctx->WriteRegisterFromUnsigned (r2_info, raw_value))
+                    set_it_simple = true;
+            }
+            else
+            {
+                uint32_t raw_value = data.GetMaxU32(&offset, 4);
+
+                if (reg_ctx->WriteRegisterFromUnsigned (r2_info, raw_value))
+                {
+                    const RegisterInfo *r3_info = reg_ctx->GetRegisterInfoByName("r3", 0);
+                    uint32_t raw_value = data.GetMaxU32(&offset, num_bytes - offset);
+
+                    if (reg_ctx->WriteRegisterFromUnsigned (r3_info, raw_value))
+                        set_it_simple = true;
+                }
+            }
+        }
+        else
+        {
+            error.SetErrorString("We don't support returning longer than 64 bit integer values at present.");
+        }
+    }
+    else if (clang_type.IsFloatingPointType (count, is_complex))
+    {
+        if (is_complex)
+            error.SetErrorString ("We don't support returning complex values at present");
+        else
+            error.SetErrorString ("We don't support returning float values at present");
+    }
+
+    if (!set_it_simple)
+        error.SetErrorString ("We only support setting simple integer return types at present.");
+
+    return error;
+}
+
+
+ValueObjectSP
+ABISysV_mips::GetReturnValueObjectSimple (Thread &thread, ClangASTType &return_clang_type) const
+{
+    ValueObjectSP return_valobj_sp;
+    return return_valobj_sp;
+}
+
+ValueObjectSP
+ABISysV_mips::GetReturnValueObjectImpl (Thread &thread, ClangASTType &return_clang_type) const
+{
+    ValueObjectSP return_valobj_sp;
+    Value value;
+
+    if (!return_clang_type)
+        return return_valobj_sp;
+
+    ExecutionContext exe_ctx (thread.shared_from_this());
+    if (exe_ctx.GetTargetPtr() == NULL || exe_ctx.GetProcessPtr() == NULL)
+        return return_valobj_sp;
+
+    value.SetClangType(return_clang_type);
+
+    RegisterContext *reg_ctx = thread.GetRegisterContext().get();
+    if (!reg_ctx)
+        return return_valobj_sp;
+    
+    bool is_signed;
+
+    // In MIPS register "r2" (v0) holds the integer function return values
+    const RegisterInfo *r2_reg_info = reg_ctx->GetRegisterInfoByName("r2", 0);
+    
+    if (return_clang_type.IsIntegerType (is_signed))
+    {
+        size_t bit_width = return_clang_type.GetBitSize(&thread);
+        
+        switch (bit_width)
+        {
+            default:
+                return return_valobj_sp;
+            case 64:
+            {
+                const RegisterInfo *r3_reg_info = reg_ctx->GetRegisterInfoByName("r3", 0);
+                uint64_t raw_value;
+                raw_value = reg_ctx->ReadRegisterAsUnsigned(r2_reg_info, 0) & UINT32_MAX;
+                raw_value |= ((uint64_t)(reg_ctx->ReadRegisterAsUnsigned(r3_reg_info, 0) & UINT32_MAX)) << 32;
+                if (is_signed)
+                    value.GetScalar() = (int64_t)raw_value;
+                else
+                    value.GetScalar() = (uint64_t)raw_value;
+            }
+                break;
+            case 32:
+                if (is_signed)
+                    value.GetScalar() = (int32_t)(reg_ctx->ReadRegisterAsUnsigned(r2_reg_info, 0) & UINT32_MAX);
+                else
+                    value.GetScalar() = (uint32_t)(reg_ctx->ReadRegisterAsUnsigned(r2_reg_info, 0) & UINT32_MAX);
+                break;
+            case 16:
+                if (is_signed)
+                    value.GetScalar() = (int16_t)(reg_ctx->ReadRegisterAsUnsigned(r2_reg_info, 0) & UINT16_MAX);
+                else
+                    value.GetScalar() = (uint16_t)(reg_ctx->ReadRegisterAsUnsigned(r2_reg_info, 0) & UINT16_MAX);
+                break;
+            case 8:
+                if (is_signed)
+                    value.GetScalar() = (int8_t)(reg_ctx->ReadRegisterAsUnsigned(r2_reg_info, 0) & UINT8_MAX);
+                else
+                    value.GetScalar() = (uint8_t)(reg_ctx->ReadRegisterAsUnsigned(r2_reg_info, 0) & UINT8_MAX);
+                break;
+        }
+    }
+    else if (return_clang_type.IsPointerType ())
+    {
+        uint32_t ptr = thread.GetRegisterContext()->ReadRegisterAsUnsigned(r2_reg_info, 0) & UINT32_MAX;
+        value.GetScalar() = ptr;
+    }
+    else
+    {
+        // not handled yet
+        return return_valobj_sp;
+    }
+    
+    // If we get here, we have a valid Value, so make our ValueObject out of it:
+
+    return_valobj_sp = ValueObjectConstResult::Create(thread.GetStackFrameAtIndex(0).get(),
+                                                      value,
+                                                      ConstString(""));
+    return return_valobj_sp;
+}
+
+bool
+ABISysV_mips::CreateFunctionEntryUnwindPlan (UnwindPlan &unwind_plan)
+{
+    unwind_plan.Clear();
+    unwind_plan.SetRegisterKind (eRegisterKindDWARF);
+
+    UnwindPlan::RowSP row(new UnwindPlan::Row);
+
+    // Our Call Frame Address is the stack pointer value
+    row->GetCFAValue().SetIsRegisterPlusOffset(gcc_dwarf_r29, 0);
+
+    // The previous PC is in the RA
+    row->SetRegisterLocationToRegister(gcc_dwarf_pc, gcc_dwarf_r31, true);
+    unwind_plan.AppendRow (row);
+
+    // All other registers are the same.
+
+    unwind_plan.SetSourceName ("mips at-func-entry default");
+    unwind_plan.SetSourcedFromCompiler (eLazyBoolNo);
+    unwind_plan.SetReturnAddressRegister(gcc_dwarf_r31);
+    return true;
+}
+
+bool
+ABISysV_mips::CreateDefaultUnwindPlan (UnwindPlan &unwind_plan)
+{
+    unwind_plan.Clear();
+
+    return false;
+}
+
+bool
+ABISysV_mips::RegisterIsVolatile (const RegisterInfo *reg_info)
+{
+    return !RegisterIsCalleeSaved (reg_info);
+}
+
+bool
+ABISysV_mips::RegisterIsCalleeSaved (const RegisterInfo *reg_info)
+{
+    if (reg_info)
+    {
+        // Preserved registers are :
+        // r16-r23, r28, r29, r30, r31
+
+        int reg = ((reg_info->byte_offset) / 4);
+
+        bool save  = (reg >= 16) && (reg <= 23);
+             save |= (reg >= 28) && (reg <= 31);
+
+        return save;
+    }
+    return false;
+}
+
+void
+ABISysV_mips::Initialize()
+{
+    PluginManager::RegisterPlugin (GetPluginNameStatic(),
+                                   "System V ABI for mips targets",
+                                   CreateInstance);
+}
+
+void
+ABISysV_mips::Terminate()
+{
+    PluginManager::UnregisterPlugin (CreateInstance);
+}
+
+lldb_private::ConstString
+ABISysV_mips::GetPluginNameStatic()
+{
+    static ConstString g_name("sysv-mips");
+    return g_name;
+}
+
+//------------------------------------------------------------------
+// PluginInterface protocol
+//------------------------------------------------------------------
+lldb_private::ConstString
+ABISysV_mips::GetPluginName()
+{
+    return GetPluginNameStatic();
+}
+
+uint32_t
+ABISysV_mips::GetPluginVersion()
+{
+    return 1;
+}

source/Plugins/ABI/SysV-mips/CMakeLists.txt

+set(LLVM_NO_RTTI 1)
+
+add_lldb_library(lldbPluginABISysV_mips
+  ABISysV_mips.cpp
+  )

source/Plugins/ABI/SysV-mips/Makefile

+##===- source/Plugins/ABI/SysV-mips/Makefile -------------*- Makefile -*-===##
+# 
+#                     The LLVM Compiler Infrastructure
+#
+# This file is distributed under the University of Illinois Open Source
+# License. See LICENSE.TXT for details.
+# 
+##===----------------------------------------------------------------------===##
+
+LLDB_LEVEL := ../../../..
+LIBRARYNAME := lldbPluginABISysV_mips
+BUILD_ARCHIVE = 1
+
+include $(LLDB_LEVEL)/Makefile