From e5ff13180c7ed268d0b4b9b2279446d7fe129622 Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Pawe=C5=82=20Bylica?= <pawel.bylica@imapp.pl>
Date: Thu, 2 Oct 2014 13:04:06 +0200
Subject: [PATCH] BALANCE

---
 evmcc/Compiler.cpp          |  8 ++++++++
 evmcc/Ext.cpp               | 23 +++++++++++++++++++++++
 evmcc/Ext.h                 |  5 +++++
 evmcc/bytecode/ext_test.evm |  2 +-
 evmcc/lll/ext_test.lll      |  1 +
 5 files changed, 38 insertions(+), 1 deletion(-)

diff --git a/evmcc/Compiler.cpp b/evmcc/Compiler.cpp
index c55b33cc6..0a9c50fc6 100644
--- a/evmcc/Compiler.cpp
+++ b/evmcc/Compiler.cpp
@@ -306,6 +306,14 @@ std::unique_ptr<llvm::Module> Compiler::compile(const dev::bytes& bytecode)
 			break;
 		}
 
+		case Instruction::BALANCE:
+		{
+			auto address = stack.pop();
+			auto value = ext.balance(address);
+			stack.push(value);
+			break;
+		}
+
 		case Instruction::CALLER:
 		{
 			auto value = ext.caller();
diff --git a/evmcc/Ext.cpp b/evmcc/Ext.cpp
index 0c38f73d3..a9013cbc5 100644
--- a/evmcc/Ext.cpp
+++ b/evmcc/Ext.cpp
@@ -3,6 +3,7 @@
 
 #include <llvm/IR/Function.h>
 #include <llvm/IR/TypeBuilder.h>
+#include <llvm/IR/IntrinsicInst.h>
 
 #include "Utils.h"
 
@@ -15,6 +16,7 @@
 using namespace llvm;
 using llvm::types::i;
 using Linkage = llvm::GlobalValue::LinkageTypes;
+using dev::h256;
 
 namespace evmcc
 {
@@ -70,6 +72,8 @@ Ext::Ext(llvm::IRBuilder<>& _builder)
 	m_store = Function::Create(TypeBuilder<void(i<256>*, i<256>*), true>::get(ctx), Linkage::ExternalLinkage, "ext_store", module);
 	m_setStore = Function::Create(TypeBuilder<void(i<256>*, i<256>*), true>::get(ctx), Linkage::ExternalLinkage, "ext_setStore", module);
 	m_calldataload = Function::Create(TypeBuilder<void(i<256>*, i<256>*), true>::get(ctx), Linkage::ExternalLinkage, "ext_calldataload", module);
+	m_balance = Function::Create(TypeBuilder<void(i<256>*, i<256>*), true>::get(ctx), Linkage::ExternalLinkage, "ext_balance", module);
+	m_bswap = Intrinsic::getDeclaration(module, Intrinsic::bswap, i256Ty);
 
 	m_builder.CreateCall(m_init, m_data);
 }
@@ -108,6 +112,19 @@ Value* Ext::calldataload(Value* _index)
 	return m_builder.CreateLoad(m_args[1]);
 }
 
+Value* Ext::bswap(Value* _value)
+{
+	return m_builder.CreateCall(m_bswap, _value);
+}
+
+Value* Ext::balance(Value* _address)
+{
+	auto address = bswap(_address); // to BigEndian	// TODO: I don't get it. It seems not needed
+	m_builder.CreateStore(address, m_args[0]);
+	m_builder.CreateCall(m_balance, m_args);
+	return m_builder.CreateLoad(m_args[1]);
+}
+
 extern "C"
 {
 
@@ -146,6 +163,12 @@ EXPORT void ext_calldataload(i256* _index, i256* _value)
 	// TODO: It all can be done by adding padding to data or by using min() algorithm without branch
 }
 
+EXPORT void ext_balance(h256* _address, i256* _value)
+{
+	auto u = g_ext->balance(dev::right160(*_address));
+	*_value = eth2llvm(u);
+}
+
 }
 
 }
\ No newline at end of file
diff --git a/evmcc/Ext.h b/evmcc/Ext.h
index a579dca81..1685ba259 100644
--- a/evmcc/Ext.h
+++ b/evmcc/Ext.h
@@ -26,11 +26,14 @@ public:
 	llvm::Value* calldatasize();
 	llvm::Value* gasprice();
 
+	llvm::Value* balance(llvm::Value* _address);
 	llvm::Value* calldataload(llvm::Value* _index);
 
 private:
 	llvm::Value* getDataElem(unsigned _index, const llvm::Twine& _name = "");
 
+	llvm::Value* bswap(llvm::Value*);
+
 private:
 	llvm::IRBuilder<>& m_builder;
 
@@ -40,6 +43,8 @@ private:
 	llvm::Function* m_store;
 	llvm::Function* m_setStore;
 	llvm::Function* m_calldataload;
+	llvm::Function* m_balance;
+	llvm::Function* m_bswap;
 };
 	
 
diff --git a/evmcc/bytecode/ext_test.evm b/evmcc/bytecode/ext_test.evm
index 5bcc94ba1..cdd04807f 100644
--- a/evmcc/bytecode/ext_test.evm
+++ b/evmcc/bytecode/ext_test.evm
@@ -1 +1 @@
-30333234363a600035602635601335380060016002f2
+3031333234363a600035602635601335380060016002f2
diff --git a/evmcc/lll/ext_test.lll b/evmcc/lll/ext_test.lll
index f32bfb440..b0f3a4adb 100644
--- a/evmcc/lll/ext_test.lll
+++ b/evmcc/lll/ext_test.lll
@@ -1,6 +1,7 @@
 
 (asm 
 ADDRESS
+BALANCE
 CALLER
 ORIGIN
 CALLVALUE