LLVM-- Cheat Sheet

It is a good idea to have this cheat sheet with you, e.g., by printing it, when writing LLVM-- code.

Description	Example(s)
Integer types	i1, i8, i32, i64
Structure types	{i1, i64 *, i8}
Fixed-size array type	[20 x i64]
Named types	%tuple = type {i64, i64}
Global variables	@x = global i64 10
Global string variables	@s = global [5 x i8] c"Hello"
External function declarations	declare i64 @libfun (i64 %x)
Function declarations	define i64 @foo (i64 %x){%y = add i64 %x, 1 ret i64 %y}
Comparison operators	eq, ne, sle, slt, sge, sgt
Arith/logical operators	add, sub, mul, sdiv, srem, shl, lshr, ashr, and, or, xor
Arith/logical computation	%x = add i64 %y, 42
Allocating on the stack	%ptr = alloca i32
Loading from a pointer	%val = load i32, i32* %ptr
Storing to a pointer	store i32 42, i32* %ptr
Integer comparison	%cmp = icmp eq i32 %val, 10
Calling void functions	call void @myFun(i32 %arg1, i32 %arg2)
Calling non-void functions	%z = call i8 @myFun(i32 %arg1, i32 %arg2)
Casting	%ptr2 = bitcast i32* %ptr to i8*
Address of pointer	%int_ptr = ptrtoint i32* %ptr to i64
Pointer arithmetic	%element_ptr = getelementptr i32, i32* %array, i32 3
Phi node	%res = phi i32 [ %val1, %block1 ], [ %val2, %block2 ]
Conditional branching	br i1 %x, label %L1, label %L2
Unconditional branching	br label %L
Returning a value	ret i64 42
Returning void	ret void
End of block unreachable	unreachable