Implement pointer arithmetic.

Bug swiftshader:11

Change-Id: I50bb9c6bf7bbe21630bd5f1eb5e0aa0aeb06fdb3
Reviewed-on: https://swiftshader-review.googlesource.com/7393
Tested-by: Nicolas Capens <capn@google.com>
Reviewed-by: Alexis Hétu <sugoi@google.com>
Reviewed-by: Nicolas Capens <capn@google.com>

src/OpenGL/libGLESv2/Device.cpp

diff --git a/src/OpenGL/libGLESv2/Device.cpp b/src/OpenGL/libGLESv2/Device.cpp
index f6aead7..3307f45 100644
--- a/src/OpenGL/libGLESv2/Device.cpp
+++ b/src/OpenGL/libGLESv2/Device.cpp
@@ -174,15 +174,15 @@
 	}
 
 	// This object has to be mem aligned
-	void* Device::operator new(size_t size)

-	{

-		ASSERT(size == sizeof(Device)); // This operator can't be called from a derived class

-		return sw::allocate(sizeof(Device), 16);

-	}

-

-	void Device::operator delete(void * mem)

-	{

-		sw::deallocate(mem);

+	void* Device::operator new(size_t size)
+	{
+		ASSERT(size == sizeof(Device)); // This operator can't be called from a derived class
+		return sw::allocate(sizeof(Device), 16);
+	}
+
+	void Device::operator delete(void * mem)
+	{
+		sw::deallocate(mem);
 	}
 
 	void Device::clearColor(float red, float green, float blue, float alpha, unsigned int rgbaMask)

src/Reactor/Main.cpp

diff --git a/src/Reactor/Main.cpp b/src/Reactor/Main.cpp
index b85e87c..a7aa820 100644
--- a/src/Reactor/Main.cpp
+++ b/src/Reactor/Main.cpp
@@ -20,7 +20,7 @@
 
 int reference(int *p, int y)
 {
-	int x = *p;
+	int x = p[-1];
 	int z = 4;
 
 	for(int i = 0; i < 10; i++)
@@ -41,7 +41,7 @@
 		Function<Int(Pointer<Int>, Int)> function;
 		{
 			Pointer<Int> p = function.Arg<0>();
-			Int x = *p;
+			Int x = p[-1];
 			Int y = function.Arg<1>();
 			Int z = 4;
 
@@ -60,9 +60,9 @@
 		if(routine)
 		{
 			int (*callable)(int*, int) = (int(*)(int*,int))routine->getEntry();
-			int one = 1;
-			int result = callable(&one, 2);
-			assert(result == reference(&one, 2));
+			int one[2] = {1, 0};
+			int result = callable(&one[1], 2);
+			assert(result == reference(&one[1], 2));
 		}
 	}
 

src/Reactor/SubzeroReactor.cpp

diff --git a/src/Reactor/SubzeroReactor.cpp b/src/Reactor/SubzeroReactor.cpp
index ade6e83..191f215 100644
--- a/src/Reactor/SubzeroReactor.cpp
+++ b/src/Reactor/SubzeroReactor.cpp
@@ -259,14 +259,7 @@
 		assert(arraySize == 0 && "UNIMPLEMENTED");
 
 		Ice::Type type = T(t);
-		
-		int32_t size = 0;
-		switch(type)
-		{
-		case Ice::IceType_i32: size = 4; break;
-		case Ice::IceType_i64: size = 8; break;
-		default: assert(false && "UNIMPLEMENTED" && type);
-		}
+		int size = Ice::typeWidthInBytes(type);
 
 		auto bytes = Ice::ConstantInteger32::create(::context, type, size);
 		auto address = ::function->makeVariable(T(getPointerType(t)));
@@ -490,7 +483,19 @@
 
 	Value *Nucleus::createGEP(Value *ptr, Type *type, Value *index)
 	{
-		assert(false && "UNIMPLEMENTED"); return nullptr;
+		assert(index->getType() == Ice::IceType_i32);
+
+		if(!Ice::isByteSizedType(T(type)))
+		{
+			index = createMul(index, createAssign(createConstantInt((int)Ice::typeWidthInBytes(T(type)))));
+		}
+
+		if(sizeof(void*) == 8)
+		{
+			index = createSExt(index, T(Ice::IceType_i64));
+		}
+
+		return createAdd(ptr, index);
 	}
 
 	Value *Nucleus::createAtomicAdd(Value *ptr, Value *value)
@@ -5615,7 +5620,7 @@
 
 	RValue<Pointer<Byte>> operator+(RValue<Pointer<Byte>> lhs, int offset)
 	{
-		assert(false && "UNIMPLEMENTED"); return RValue<Pointer<Byte>>(V(nullptr));
+		return lhs + RValue<Int>(Nucleus::createConstantInt(offset));
 	}
 
 	RValue<Pointer<Byte>> operator+(RValue<Pointer<Byte>> lhs, RValue<Int> offset)