carbon-lang/toolchain/docs/lower.md

Lower

Table of contents

• Overview

Overview

Lowering takes the SemIR and produces LLVM IR. At present, this is done in a single pass, although it's possible we may need to do a second pass so that we can first generate type information for function arguments.

Lowering is done per SemIR::InstBlock. This minimizes changes to the IRBuilder insertion point, something that is both expensive and potentially fragile.