From 7f8848744df95ad5d4351e4936a46ec04a1c8e75 Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Pawe=C5=82=20Bylica?= <pawel.bylica@imapp.pl>
Date: Thu, 9 Oct 2014 09:33:31 +0200
Subject: [PATCH] EXP instruction.

[Delivers #79736422]
---
 evmcc/Compiler.cpp                 |  9 +++++++++
 evmcc/Ext.cpp                      | 18 ++++++++++++++++++
 evmcc/Ext.h                        |  2 ++
 evmcc/bytecode/arithmetic_test.evm |  2 +-
 evmcc/lll/arithmetic_test.lll      |  8 ++++++++
 5 files changed, 38 insertions(+), 1 deletion(-)

diff --git a/evmcc/Compiler.cpp b/evmcc/Compiler.cpp
index c46dd72c5..880487705 100644
--- a/evmcc/Compiler.cpp
+++ b/evmcc/Compiler.cpp
@@ -274,6 +274,15 @@ std::unique_ptr<llvm::Module> Compiler::compile(const dev::bytes& bytecode)
 				break;
 			}
 
+			case Instruction::EXP:
+			{
+				auto left = stack.pop();
+				auto right = stack.pop();
+				auto ret = ext.exp(left, right);
+				stack.push(ret);
+				break;
+			}
+
 			case Instruction::NEG:
 			{
 				auto top = stack.pop();
diff --git a/evmcc/Ext.cpp b/evmcc/Ext.cpp
index 8266bd728..121103354 100644
--- a/evmcc/Ext.cpp
+++ b/evmcc/Ext.cpp
@@ -93,6 +93,7 @@ Ext::Ext(llvm::IRBuilder<>& _builder, llvm::Module* module)
 	m_call = Function::Create(FunctionType::get(m_builder.getVoidTy(), args, false), Linkage::ExternalLinkage, "ext_call", module);
 	m_bswap = Intrinsic::getDeclaration(module, Intrinsic::bswap, i256Ty);
 	m_sha3 = Function::Create(TypeBuilder<void(i<256>*, i<256>*, i<256>*), true>::get(ctx), Linkage::ExternalLinkage, "ext_sha3", module);
+	m_exp = Function::Create(TypeBuilder<void(i<256>*, i<256>*, i<256>*), true>::get(ctx), Linkage::ExternalLinkage, "ext_exp", module);
 
 
 	m_builder.CreateCall(m_init, m_data);
@@ -196,6 +197,15 @@ llvm::Value* Ext::sha3(llvm::Value* _inOff, llvm::Value* _inSize)
 	return hash;
 }
 
+llvm::Value* Ext::exp(llvm::Value* _left, llvm::Value* _right)
+{
+	m_builder.CreateStore(_left, m_args[0]);
+	m_builder.CreateStore(_right, m_arg2);
+	llvm::Value* args[] = {m_args[0], m_arg2, m_args[1]};
+	m_builder.CreateCall(m_exp, args);
+	return m_builder.CreateLoad(m_args[1]);
+}
+
 extern "C"
 {
 
@@ -308,6 +318,14 @@ EXPORT void ext_sha3(i256* _inOff, i256* _inSize, i256* _ret)
 	*_ret = *reinterpret_cast<i256*>(&hash);
 }
 
+EXPORT void ext_exp(i256* _left, i256* _right, i256* _ret)
+{
+	dev::bigint left = llvm2eth(*_left);
+	dev::bigint right = llvm2eth(*_right);
+	auto ret = static_cast<u256>(boost::multiprecision::powm(left, right, dev::bigint(2) << 256));
+	*_ret = eth2llvm(ret);
+}
+
 }
 
 }
diff --git a/evmcc/Ext.h b/evmcc/Ext.h
index 7801d0540..302991854 100644
--- a/evmcc/Ext.h
+++ b/evmcc/Ext.h
@@ -39,6 +39,7 @@ public:
 	llvm::Value* call(llvm::Value* _gas, llvm::Value* _receiveAddress, llvm::Value* _value, llvm::Value* _inOff, llvm::Value* _inSize, llvm::Value* _outOff, llvm::Value* _outSize);
 
 	llvm::Value* sha3(llvm::Value* _inOff, llvm::Value* _inSize);
+	llvm::Value* exp(llvm::Value* _left, llvm::Value* _right);
 
 private:
 	llvm::Value* getDataElem(unsigned _index, const llvm::Twine& _name = "");
@@ -66,6 +67,7 @@ private:
 	llvm::Function* m_call;
 	llvm::Function* m_bswap;
 	llvm::Function* m_sha3;
+	llvm::Function* m_exp;
 };
 	
 
diff --git a/evmcc/bytecode/arithmetic_test.evm b/evmcc/bytecode/arithmetic_test.evm
index 67e86b310..c7a029f52 100644
--- a/evmcc/bytecode/arithmetic_test.evm
+++ b/evmcc/bytecode/arithmetic_test.evm
@@ -1 +1 @@
-60016001900160070260050160029004600490066021900560150160030260059007600303
+60016001900160070260050160029004600490066021900560150160030260059007600303600960110860005460086000f2
diff --git a/evmcc/lll/arithmetic_test.lll b/evmcc/lll/arithmetic_test.lll
index e2c14d4c7..4757a7420 100644
--- a/evmcc/lll/arithmetic_test.lll
+++ b/evmcc/lll/arithmetic_test.lll
@@ -26,4 +26,12 @@ SWAP1
 SMOD;; 3
 3
 SUB ;; 0
+9
+17
+EXP ;; 17^9
+0
+MSTORE
+8
+0
+RETURN
 )
\ No newline at end of file