[all-commits] [llvm/llvm-project] 4c96b3: [X86] -fpatchable-function-entry=N, 0: place patch ...

[Fangrui Song via All-commits]

  Branch: refs/heads/release/10.x
  Home:   https://github.com/llvm/llvm-project
  Commit: 4c96b369a074e93a0be536dd795d3f245ef6f18b
      https://github.com/llvm/llvm-project/commit/4c96b369a074e93a0be536dd795d3f245ef6f18b
  Author: Fangrui Song <maskray at google.com>
  Date:   2020-02-05 (Wed, 05 Feb 2020)

  Changed paths:
    M llvm/lib/Target/X86/X86MCInstLower.cpp
    M llvm/test/CodeGen/AArch64/patchable-function-entry-bti.ll
    M llvm/test/CodeGen/X86/patchable-function-entry-ibt.ll

  Log Message:
  -----------
  [X86] -fpatchable-function-entry=N,0: place patch label after ENDBR{32,64}

Similar to D73680 (AArch64 BTI).

A local linkage function whose address is not taken does not need ENDBR32/ENDBR64. Placing the patch label after ENDBR32/ENDBR64 has the advantage that code does not need to differentiate whether the function has an initial ENDBR.

Also, add 32-bit tests and test that .cfi_startproc is at the function
entry. The line information has a general implementation and is tested
by AArch64/patchable-function-entry-empty.mir

Reviewed By: nickdesaulniers

Differential Revision: https://reviews.llvm.org/D73760

(cherry picked from commit 8ff86fcf4c038c7156ed4f01e7ed35cae49489e2)