[PATCH] D132531: [AArch64] Reserve more physical registers

[Guozhi Wei via Phabricator via cfe-commits]

Carrot added a comment.

A reserved physical register doesn't mean it can't be used by compiler/linker, it just means it can't be used by register allocator, see the comments in TargetRegisterInfo::getReservedRegs(). The most common example is the stack pointer. So when we reserve X8, X16, X17 and X19, it means we can't allocate them to virtual registers, compiler/linker can still use X8 to pass return address, and use X16 and X17 in a veneer.


Repository:
  rG LLVM Github Monorepo

CHANGES SINCE LAST ACTION
  https://reviews.llvm.org/D132531/new/

https://reviews.llvm.org/D132531