Squashed 'spasm/' content from commit 08ee95d

git-subtree-dir: spasm
git-subtree-split: 08ee95d89054ba0d33697d613799a0a013aedf89

1 files changed, 79 insertions, 0 deletions

diff --git a/src/asm/assembler.cpp b/src/asm/assembler.cpp
new file mode 100644
index 0000000..25ed377
--- /dev/null
+++ b/src/asm/assembler.cpp
@@ -0,0 +1,79 @@
+#include <cassert>
+
+#include "assembler.hpp"
+#include "bytecode.hpp"
+#include "symbol.hpp"
+#include "tokenizer.hpp"
+
+namespace SpasmImpl
+{
+namespace ASM
+{
+Assembler::Assembler(Lexer::Tokenizer& tokenizer, Bytecode_Stream& bytecode)
+    : _tokenizer(&tokenizer), _bytecode(&bytecode)
+{
+}
+
+void Assembler::assemble()
+{
+    Lexer::Token token = _tokenizer->next_token();
+
+    while (token.type() != Lexer::Token::endinput)
+    {
+        switch (token.type())
+        {
+            case Lexer::Token::ident:
+                assemble_identifier(token);
+                break;
+            case Lexer::Token::label:
+                token = _tokenizer->next_token();
+                assert(token.type() == Lexer::Token::ident);
+                _symbols.define(token.value_str(), _bytecode->size());
+                break;
+            case Lexer::Token::integer:
+            case Lexer::Token::xinteger:
+                _bytecode->push_integer(token.value_int());
+                break;
+            default:
+                _bytecode->push_opcode((Bytecode_Stream::Opcode_t)token.type());
+        }
+
+        token = _tokenizer->next_token();
+    }
+
+    Symbol_Table::const_iterator i = _symbols.begin();
+    while (i != _symbols.end())
+    {
+        backpatch(i->second);
+        ++i;
+    }
+}
+
+void Assembler::backpatch(const Symbol* symbol)
+{
+    Symbol::Positions_t::const_iterator i = symbol->positions_begin();
+    while (i != symbol->positions_end())
+    {
+        _bytecode->set_location(*i, symbol->definition());
+        ++i;
+    }
+}
+
+void Assembler::assemble_identifier(const Lexer::Token& token)
+{
+    Symbol* symbol = _symbols.insert(token.value_str(), _bytecode->size());
+    _bytecode->push_location(symbol->definition());
+}
+
+bool compile(std::istream& istr, Bytecode_Memory& bytecode)
+{
+    Lexer::Tokenizer tokenizer(istr);
+    Assembler assembler(tokenizer, bytecode);
+
+    assembler.assemble();
+
+    return true;
+}
+
+}  // namespace ASM
+}  // namespace SpasmImpl