[RFC] Syncing Asm Goto with Outputs with GCC

Code Generation Common Infrastructure
6

PDF of my RFC [RFC] handling outputs along indirect edges of callbr - callbrpad.pdf (128.2 KB)

Patch series:

  1. [IR] add new callbrpad instruction
  2. [Clang] refactor CodeGenFunction::EmitAsmStmt NFC
  3. [Clang] support for outputs along indirect edges of asm goto

cc @rnk @jyknight @efriedma-quic @topperc @nikic @arsenm