Refactored the expression parser so that the IR

and the JITted code are managed by a standalone
class that handles memory management itself.

I have removed RecordingMemoryManager and
ProcessDataAllocator, which filled similar roles
and had confusing ownership, with a common class
called IRExecutionUnit.  The IRExecutionUnit
manages all allocations ever made for an expression
and frees them when it goes away.  It also contains
the code generator and can vend the Module for an
expression to other clases.

The end goal here is to make the output of the
expression parser re-usable; that is, to avoid
re-parsing when re-parsing isn't necessary.

I've also cleaned up some code and used weak pointers
in more places.  Please let me know if you see any
leaks; I checked myself as well but I might have
missed a case.

llvm-svn: 177364

1 files changed, 33 insertions, 27 deletions

diff --git a/lldb/source/Expression/IRForTarget.cpp b/lldb/source/Expression/IRForTarget.cpp
index c7c96f73fbd..279e034d832 100644
--- a/lldb/source/Expression/IRForTarget.cpp
+++ b/lldb/source/Expression/IRForTarget.cpp
@@ -22,12 +22,14 @@
 
 #include "clang/AST/ASTContext.h"
 
-#include "lldb/Core/ConstString.h"
 #include "lldb/Core/dwarf.h"
+#include "lldb/Core/ConstString.h"
+#include "lldb/Core/DataBufferHeap.h"
 #include "lldb/Core/Log.h"
 #include "lldb/Core/Scalar.h"
 #include "lldb/Core/StreamString.h"
 #include "lldb/Expression/ClangExpressionDeclMap.h"
+#include "lldb/Expression/IRExecutionUnit.h"
 #include "lldb/Expression/IRInterpreter.h"
 #include "lldb/Host/Endian.h"
 #include "lldb/Symbol/ClangASTContext.h"
@@ -38,19 +40,32 @@ using namespace llvm;
 
 static char ID;
 
-IRForTarget::StaticDataAllocator::StaticDataAllocator()
+IRForTarget::StaticDataAllocator::StaticDataAllocator(lldb_private::IRExecutionUnit &execution_unit) :
+    m_execution_unit(execution_unit),
+    m_allocation(LLDB_INVALID_ADDRESS)
 {
 }
 
-IRForTarget::StaticDataAllocator::~StaticDataAllocator()
+lldb::addr_t IRForTarget::StaticDataAllocator::Allocate()
 {
+    lldb_private::Error err;
+    
+    if (m_allocation != LLDB_INVALID_ADDRESS)
+    {
+        m_execution_unit.FreeNow(m_allocation);
+        m_allocation = LLDB_INVALID_ADDRESS;
+    }
+    
+    m_allocation = m_execution_unit.WriteNow((const uint8_t*)m_stream_string.GetData(), m_stream_string.GetSize(), err);
+
+    return m_allocation;
 }
 
 IRForTarget::IRForTarget (lldb_private::ClangExpressionDeclMap *decl_map,
                           bool resolve_vars,
                           lldb_private::ExecutionPolicy execution_policy,
                           lldb::ClangExpressionVariableSP &const_result,
-                          StaticDataAllocator *data_allocator,
+                          lldb_private::IRExecutionUnit &execution_unit,
                           lldb_private::Stream *error_stream,
                           const char *func_name) :
     ModulePass(ID),
@@ -60,7 +75,7 @@ IRForTarget::IRForTarget (lldb_private::ClangExpressionDeclMap *decl_map,
     m_func_name(func_name),
     m_module(NULL),
     m_decl_map(decl_map),
-    m_data_allocator(data_allocator),
+    m_data_allocator(execution_unit),
     m_CFStringCreateWithBytes(NULL),
     m_sel_registerName(NULL),
     m_const_result(const_result),
@@ -1559,7 +1574,7 @@ IRForTarget::MaterializeInternalVariable (GlobalVariable *global_variable)
     if (global_variable == m_reloc_placeholder)
         return true;
     
-    uint64_t offset = m_data_allocator->GetStream().GetSize();
+    uint64_t offset = m_data_allocator.GetStream().GetSize();
     
     llvm::Type *variable_type = global_variable->getType();
     
@@ -1572,7 +1587,7 @@ IRForTarget::MaterializeInternalVariable (GlobalVariable *global_variable)
     
     const size_t mask = (align - 1);
     uint64_t aligned_offset = (offset + mask) & ~mask;
-    m_data_allocator->GetStream().PutNHex8(aligned_offset - offset, 0);
+    m_data_allocator.GetStream().PutNHex8(aligned_offset - offset, 0);
     offset = aligned_offset;
     
     lldb_private::DataBufferHeap data(size, '\0');
@@ -1581,7 +1596,7 @@ IRForTarget::MaterializeInternalVariable (GlobalVariable *global_variable)
         if (!MaterializeInitializer(data.GetBytes(), initializer))
             return false;
     
-    m_data_allocator->GetStream().Write(data.GetBytes(), data.GetByteSize());
+    m_data_allocator.GetStream().Write(data.GetBytes(), data.GetByteSize());
     
     Constant *new_pointer = BuildRelocation(variable_type, offset);
         
@@ -1960,9 +1975,6 @@ IRForTarget::ReplaceStrings ()
 {
     lldb::LogSP log(lldb_private::GetLogIfAllCategoriesSet (LIBLLDB_LOG_EXPRESSIONS));
     
-    if (!m_data_allocator)
-        return true; // hope for the best; some clients may not want static allocation!
-    
     typedef std::map <GlobalVariable *, size_t> OffsetsTy;
     
     OffsetsTy offsets;
@@ -2014,9 +2026,9 @@ IRForTarget::ReplaceStrings ()
             str = gc_array->getAsString();
         }
             
-        offsets[gv] = m_data_allocator->GetStream().GetSize();
+        offsets[gv] = m_data_allocator.GetStream().GetSize();
         
-        m_data_allocator->GetStream().Write(str.c_str(), str.length() + 1);
+        m_data_allocator.GetStream().Write(str.c_str(), str.length() + 1);
     }
     
     Type *char_ptr_ty = Type::getInt8PtrTy(m_module->getContext());
@@ -2083,9 +2095,6 @@ bool
 IRForTarget::ReplaceStaticLiterals (llvm::BasicBlock &basic_block)
 {
     lldb::LogSP log(lldb_private::GetLogIfAllCategoriesSet (LIBLLDB_LOG_EXPRESSIONS));
-        
-    if (!m_data_allocator)
-        return true;
     
     typedef SmallVector <Value*, 2> ConstantList;
     typedef SmallVector <llvm::Instruction*, 2> UserList;
@@ -2156,7 +2165,7 @@ IRForTarget::ReplaceStaticLiterals (llvm::BasicBlock &basic_block)
             
             lldb_private::DataBufferHeap data(operand_data_size, 0);
             
-            if (lldb::endian::InlHostByteOrder() != m_data_allocator->GetStream().GetByteOrder())
+            if (lldb::endian::InlHostByteOrder() != m_data_allocator.GetStream().GetByteOrder())
             {
                 uint8_t *data_bytes = data.GetBytes();
                 
@@ -2172,16 +2181,16 @@ IRForTarget::ReplaceStaticLiterals (llvm::BasicBlock &basic_block)
                 memcpy(data.GetBytes(), operand_raw_data, operand_data_size);
             }
             
-            uint64_t offset = m_data_allocator->GetStream().GetSize();
+            uint64_t offset = m_data_allocator.GetStream().GetSize();
             
             size_t align = m_target_data->getPrefTypeAlignment(operand_type);
             
             const size_t mask = (align - 1);
             uint64_t aligned_offset = (offset + mask) & ~mask;
-            m_data_allocator->GetStream().PutNHex8(aligned_offset - offset, 0);
+            m_data_allocator.GetStream().PutNHex8(aligned_offset - offset, 0);
             offset = aligned_offset;
             
-            m_data_allocator->GetStream().Write(data.GetBytes(), operand_data_size);
+            m_data_allocator.GetStream().Write(data.GetBytes(), operand_data_size);
             
             llvm::Type *fp_ptr_ty = operand_constant_fp->getType()->getPointerTo();
             
@@ -2603,16 +2612,13 @@ IRForTarget::BuildRelocation(llvm::Type *type,
 
 bool 
 IRForTarget::CompleteDataAllocation ()
-{
-    if (!m_data_allocator)
-        return true;
-    
+{    
     lldb::LogSP log(lldb_private::GetLogIfAllCategoriesSet (LIBLLDB_LOG_EXPRESSIONS));
 
-    if (!m_data_allocator->GetStream().GetSize())
+    if (!m_data_allocator.GetStream().GetSize())
         return true;
     
-    lldb::addr_t allocation = m_data_allocator->Allocate();
+    lldb::addr_t allocation = m_data_allocator.Allocate();
     
     if (log)
     {
@@ -2622,7 +2628,7 @@ IRForTarget::CompleteDataAllocation ()
             log->Printf("Failed to allocate static data");
     }
     
-    if (!allocation)
+    if (!allocation || allocation == LLDB_INVALID_ADDRESS)
         return false;
     
     IntegerType *intptr_ty = Type::getIntNTy(m_module->getContext(),