Function LLVMGetFirstBasicBlock 

pub unsafe extern "C" fn LLVMGetFirstBasicBlock(
    Fn: LLVMValueRef,
) -> LLVMBasicBlockRef

Obtain the first basic block in a function.

The returned basic block can be used as an iterator. You will likely eventually call into LLVMGetNextBasicBlock() with it.

@see llvm::Function::begin()