nedgrady

int i = 128;

// Push the value 128 (0x00000080) onto the stack
IL_0001:  ldc.i4      80 00 00 00
// Store our 128 at location 0 (where the compiler has chosen for i to live).
IL_0002:  stloc.0	// i

System.Console.WriteLine(i + 10);
// Push the value of i back onto the stack.
IL_0007:  ldloc.0     // i

nedgrady

// CSharp:
int i = 128;

// Compiles into:
// Push the value 128 (0x00000080) onto the stack
IL_0001:  ldc.i4      80 00 00 00
// Store our 128 at location 0 (where the compiler has chosen for i to live).
IL_0002:  stloc.0	// i

nedgrady

System.Console.WriteLine(i + 10);

// Push the value of i back onto the stack.
IL_0007:  ldloc.0     // i
// Push 10 (0xA) onto the stack
IL_0008:  ldc.i4.s    0A
// Add the two top values, leaving the result on top of the stack
IL_000A:  add
// Call the static System.Console.WriteLine method, notice we’re passing a 
// parameter by pushing its value onto the stack before a call instruction.

nedgrady

class MyClass { }

// Compiles into...

// Constructor declaration, remember a construcor is just a method under the hood.
MyClass..ctor:
// Push argument 0 onto the stack. Any CIL instance methods have an Argument 0
// which is a pointer to the current object the method being is called upon, 'this', in C#
IL_0000:  ldarg.0
// Call our base class constructor on this.

nedgrady

class MyClass : object
{
	public MyClass()
		: base()
	{ }
}

nedgrady

// call our first method, leaving the argument result on the stack top
IL_0001:  call        UserQuery.SideEffectOne
// jump to IL_000F if the first method returned false, pop from the stack
IL_0006:  brfalse.s   IL_000F
// call our second method, leaving the argument result on the stack top
IL_0008:  call        UserQuery.SideEffectTwo
// always jump to IL_0010, (no value popped!)
IL_000D:  br.s        IL_0010
// load integer value of 0 on to the stack top
IL_000F:  ldc.i4.0

nedgrady

IL_0001:  call        SideEffectOne	[0]
IL_0006:  brfalse.s   IL_000F		[]
IL_000F:  ldc.i4.0			[0]
IL_0010:  stloc.0     // p = 0		[] 

nedgrady

IL_0001:  call        SideEffectOne	[1]
IL_0006:  brfalse.s   IL_000F		[]
IL_0008:  call        SideEffectTwo	[p]
IL_000D:  br.s        IL_0010		[p]
IL_0010:  stloc.0     // p		[]

nedgrady

bool p = ...;
bool q = ...;
bool r = p && q;

// p and q setup here…
// push p onto stack top
IL_0005:  ldloc.0     // p		[p]
// push q onto stack top
IL_0006:  ldloc.1     // q		[p, q]
// AND together top two stack values

nedgrady

IL_0005:  ldloc.0     // p
IL_0006:  brfalse.s   IL_000B
IL_0008:  ldloc.1     // q
IL_0009:  br.s        IL_000D
IL_000B:  ldc.i4.0    
IL_000D:  stloc.2     // r