[all-commits] [llvm/llvm-project] 8d7ccb: Set the floating point status register as reserved

[Pengfei Wang via All-commits]

  Branch: refs/heads/master
  Home:   https://github.com/llvm/llvm-project
  Commit: 8d7ccb37440e11552cb4a0bb989ddee5031700a4
      https://github.com/llvm/llvm-project/commit/8d7ccb37440e11552cb4a0bb989ddee5031700a4
  Author: Pengfei Wang <pengfei.wang at intel.com>
  Date:   2019-11-03 (Sun, 03 Nov 2019)

  Changed paths:
    M llvm/lib/Target/X86/X86RegisterInfo.cpp
    M llvm/test/CodeGen/X86/pr34080-2.ll

  Log Message:
  -----------
   Set the floating point status register as reserved

Summary:
This patch sets the FPSW (X87 floating-point status register) as a reserved
physical register and fix the test failure caused by [[ https://reviews.llvm.org/D68854| D68854 ]].

Before this patch, some tests will fail because it implicit uses FPSW without
define it. Setting the FPSW as a reserved physical register will skip liveness
analysis because it is always live.

Reviewers: pengfei, craig.topper

Reviewed By: craig.topper

Subscribers: craig.topper, hiraditya, llvm-commits

Patch by LiuChen.

Differential Revision: https://reviews.llvm.org/D69784