1
0
mirror of https://github.com/RPCS3/llvm-mirror.git synced 2024-11-22 18:54:02 +01:00
llvm-mirror/test/CodeGen/AArch64/machine-outliner-outline-bti.ll
Momchil Velikov e1e1463f1c [AArch64] PAC/BTI code generation for LLVM generated functions
PAC/BTI-related codegen in the AArch64 backend is controlled by a set
of LLVM IR function attributes, added to the function by Clang, based
on command-line options and GCC-style function attributes. However,
functions, generated in the LLVM middle end (for example,
asan.module.ctor or __llvm_gcov_write_out) do not get any attributes
and the backend incorrectly does not do any PAC/BTI code generation.

This patch record the default state of PAC/BTI codegen in a set of
LLVM IR module-level attributes, based on command-line options:

* "sign-return-address", with non-zero value means generate code to
  sign return addresses (PAC-RET), zero value means disable PAC-RET.

* "sign-return-address-all", with non-zero value means enable PAC-RET
  for all functions, zero value means enable PAC-RET only for
  functions, which spill LR.

* "sign-return-address-with-bkey", with non-zero value means use B-key
  for signing, zero value mean use A-key.

This set of attributes are always added for AArch64 targets (as
opposed, for example, to interpreting a missing attribute as having a
value 0) in order to be able to check for conflicts when combining
module attributed during LTO.

Module-level attributes are overridden by function level attributes.
All the decision making about whether to not to generate PAC and/or
BTI code is factored out into AArch64FunctionInfo, there shouldn't be
any places left, other than AArch64FunctionInfo, which directly
examine PAC/BTI attributes, except AArch64AsmPrinter.cpp, which
is/will-be handled by a separate patch.

Differential Revision: https://reviews.llvm.org/D85649
2020-09-25 11:47:14 +01:00

23 lines
598 B
LLVM

; RUN: llc -mtriple aarch64--none-eabi < %s | FileCheck %s
; The BTI instruction cannot be outlined, because it needs to be the very first
; instruction executed after an indirect call.
@g = hidden global i32 0, align 4
define hidden void @foo() minsize "branch-target-enforcement"="true" {
entry:
; CHECK: hint #34
; CHECK: b OUTLINED_FUNCTION_0
store volatile i32 1, i32* @g, align 4
ret void
}
define hidden void @bar() minsize "branch-target-enforcement"="true" {
entry:
; CHECK: hint #34
; CHECK: b OUTLINED_FUNCTION_0
store volatile i32 1, i32* @g, align 4
ret void
}