Simplify the CreateDefaultUnwindPlan methods for the x86 and arm unwinders

a bit -- we're creating the UnwindPlan here, we can set the register set to
whatever is convenient for us, no need to handle different register sets.

A handful of small comment fixes I noticed while reading through the code.

llvm-svn: 159924

3 files changed, 17 insertions, 70 deletions

diff --git a/lldb/source/Plugins/ABI/MacOSX-arm/ABIMacOSX_arm.cpp b/lldb/source/Plugins/ABI/MacOSX-arm/ABIMacOSX_arm.cpp
index 9ec2e64e0e8..9ca35fa9506 100644
--- a/lldb/source/Plugins/ABI/MacOSX-arm/ABIMacOSX_arm.cpp
+++ b/lldb/source/Plugins/ABI/MacOSX-arm/ABIMacOSX_arm.cpp
@@ -538,10 +538,10 @@ ABIMacOSX_arm::CreateFunctionEntryUnwindPlan (UnwindPlan &unwind_plan)
 
     UnwindPlan::Row row;
     
-    // Our previous Call Frame Address is the stack pointer
+    // Our Call Frame Address is the stack pointer value
     row.SetCFARegister (sp_reg_num);
     
-    // Our previous PC is in the LR
+    // The previous PC is in the LR
     row.SetRegisterLocationToRegister(pc_reg_num, lr_reg_num, true);
     unwind_plan.AppendRow (row);
     
@@ -554,36 +554,15 @@ ABIMacOSX_arm::CreateFunctionEntryUnwindPlan (UnwindPlan &unwind_plan)
 bool
 ABIMacOSX_arm::CreateDefaultUnwindPlan (UnwindPlan &unwind_plan)
 {
-    uint32_t reg_kind = unwind_plan.GetRegisterKind();
-    uint32_t fp_reg_num = LLDB_INVALID_REGNUM;
-    uint32_t sp_reg_num = LLDB_INVALID_REGNUM;
-    uint32_t pc_reg_num = LLDB_INVALID_REGNUM;
-    
-    switch (reg_kind)
-    {
-        case eRegisterKindDWARF:
-        case eRegisterKindGCC:
-            fp_reg_num = dwarf_r7; // apple uses r7 for all frames. Normal arm uses r11
-            sp_reg_num = dwarf_sp;
-            pc_reg_num = dwarf_pc;
-            break;
-            
-        case eRegisterKindGeneric:
-            fp_reg_num = LLDB_REGNUM_GENERIC_FP;
-            sp_reg_num = LLDB_REGNUM_GENERIC_SP;
-            pc_reg_num = LLDB_REGNUM_GENERIC_PC;
-            break;
-    }
-    
-    if (fp_reg_num == LLDB_INVALID_REGNUM ||
-        sp_reg_num == LLDB_INVALID_REGNUM ||
-        pc_reg_num == LLDB_INVALID_REGNUM)
-        return false;
+    uint32_t fp_reg_num = dwarf_r7; // apple uses r7 for all frames. Normal arm uses r11;
+    uint32_t sp_reg_num = dwarf_sp;
+    uint32_t pc_reg_num = dwarf_pc;
     
     UnwindPlan::Row row;    
     const int32_t ptr_size = 4;
     
-    unwind_plan.SetRegisterKind (eRegisterKindGeneric);
+    unwind_plan.Clear ();
+    unwind_plan.SetRegisterKind (eRegisterKindDWARF);
     row.SetCFARegister (fp_reg_num);
     row.SetCFAOffset (2 * ptr_size);
     row.SetOffset (0);
@@ -601,7 +580,7 @@ ABIMacOSX_arm::RegisterIsVolatile (const RegisterInfo *reg_info)
 {
     if (reg_info)
     {
-        // Volatile registers include: ebx, ebp, esi, edi, esp, eip
+        // Volatile registers include: r0, r1, r2, r3, r9, r12, r13
         const char *name = reg_info->name;
         if (name[0] == 'r')
         {
diff --git a/lldb/source/Plugins/ABI/MacOSX-i386/ABIMacOSX_i386.cpp b/lldb/source/Plugins/ABI/MacOSX-i386/ABIMacOSX_i386.cpp
index f5cd7ca7dff..2998e6bbf82 100644
--- a/lldb/source/Plugins/ABI/MacOSX-i386/ABIMacOSX_i386.cpp
+++ b/lldb/source/Plugins/ABI/MacOSX-i386/ABIMacOSX_i386.cpp
@@ -820,47 +820,15 @@ ABIMacOSX_i386::CreateFunctionEntryUnwindPlan (UnwindPlan &unwind_plan)
 bool
 ABIMacOSX_i386::CreateDefaultUnwindPlan (UnwindPlan &unwind_plan)
 {
-    uint32_t reg_kind = unwind_plan.GetRegisterKind();
-    uint32_t fp_reg_num = LLDB_INVALID_REGNUM;
-    uint32_t sp_reg_num = LLDB_INVALID_REGNUM;
-    uint32_t pc_reg_num = LLDB_INVALID_REGNUM;
+    uint32_t fp_reg_num = dwarf_ebp;
+    uint32_t sp_reg_num = dwarf_esp;
+    uint32_t pc_reg_num = dwarf_eip;
     
-    switch (reg_kind)
-    {
-        case eRegisterKindDWARF:
-            fp_reg_num = dwarf_ebp;
-            sp_reg_num = dwarf_esp;
-            pc_reg_num = dwarf_eip;
-            break;
-            
-        case eRegisterKindGCC:
-            fp_reg_num = gcc_ebp;
-            sp_reg_num = gcc_esp;
-            pc_reg_num = gcc_eip;
-            break;
-            
-        case eRegisterKindGDB:
-            fp_reg_num = gdb_ebp;
-            sp_reg_num = gdb_esp;
-            pc_reg_num = gdb_eip;
-            break;
-            
-        case eRegisterKindGeneric:
-            fp_reg_num = LLDB_REGNUM_GENERIC_FP;
-            sp_reg_num = LLDB_REGNUM_GENERIC_SP;
-            pc_reg_num = LLDB_REGNUM_GENERIC_PC;
-            break;
-    }
-    
-    if (fp_reg_num == LLDB_INVALID_REGNUM ||
-        sp_reg_num == LLDB_INVALID_REGNUM ||
-        pc_reg_num == LLDB_INVALID_REGNUM)
-        return false;
-
     UnwindPlan::Row row;    
     const int32_t ptr_size = 4;
 
-    unwind_plan.SetRegisterKind (eRegisterKindGeneric);
+    unwind_plan.Clear ();
+    unwind_plan.SetRegisterKind (eRegisterKindDWARF);
     row.SetCFARegister (fp_reg_num);
     row.SetCFAOffset (2 * ptr_size);
     row.SetOffset (0);
diff --git a/lldb/source/Plugins/UnwindAssembly/InstEmulation/UnwindAssemblyInstEmulation.cpp b/lldb/source/Plugins/UnwindAssembly/InstEmulation/UnwindAssemblyInstEmulation.cpp
index 37ddfb1a998..6d2b0a54b6a 100644
--- a/lldb/source/Plugins/UnwindAssembly/InstEmulation/UnwindAssemblyInstEmulation.cpp
+++ b/lldb/source/Plugins/UnwindAssembly/InstEmulation/UnwindAssemblyInstEmulation.cpp
@@ -30,7 +30,7 @@ using namespace lldb_private;
 
 
 //-----------------------------------------------------------------------------------------------
-//  UnwindAssemblyParser_x86 method definitions 
+//  UnwindAssemblyInstEmulation method definitions 
 //-----------------------------------------------------------------------------------------------
 
 bool
@@ -71,9 +71,6 @@ UnwindAssemblyInstEmulation::GetNonCallSiteUnwindPlanFromAssembly (AddressRange&
             const uint32_t addr_byte_size = m_arch.GetAddressByteSize();
             const bool show_address = true;
             const bool show_bytes = true;
-            // Initialize the CFA with a known value. In the 32 bit case
-            // it will be 0x80000000, and in the 64 bit case 0x8000000000000000.
-            // We use the address byte size to be safe for any future addresss sizes
             m_inst_emulator_ap->GetRegisterInfo (unwind_plan.GetRegisterKind(), 
                                                  unwind_plan.GetInitialCFARegister(), 
                                                  m_cfa_reg_info);
@@ -82,6 +79,9 @@ UnwindAssemblyInstEmulation::GetNonCallSiteUnwindPlanFromAssembly (AddressRange&
             m_register_values.clear();
             m_pushed_regs.clear();
 
+            // Initialize the CFA with a known value. In the 32 bit case
+            // it will be 0x80000000, and in the 64 bit case 0x8000000000000000.
+            // We use the address byte size to be safe for any future addresss sizes
             m_initial_sp = (1ull << ((addr_byte_size * 8) - 1));
             RegisterValue cfa_reg_value;
             cfa_reg_value.SetUInt (m_initial_sp, m_cfa_reg_info.byte_size);