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|
# RUN: llc -verify-machineinstrs -mtriple=aarch64-none-linux-gnu \
# RUN: -start-before aarch64-sls-hardening -o - %s \
# RUN: -asm-verbose=0 \
# RUN: | FileCheck %s \
# RUN: --implicit-check-not=__llvm_slsblr_thunk_aa_x5_x8 \
# RUN: --implicit-check-not=__llvm_slsblr_thunk_ab_x5_x8 \
# RUN: --implicit-check-not=__llvm_slsblr_thunk_aaz_x5 \
# RUN: --implicit-check-not=__llvm_slsblr_thunk_abz_x5
# Pointer Authentication extension introduces more branch-with-link-to-register
# instructions for the BLR SLS hardening to handle, namely BLRAA, BLRAB, BLRAAZ
# and BLRABZ. Unlike the non-authenticating BLR instruction, BLRAA and BLRAB
# accept two register operands (almost 900 combinations for each instruction).
# For that reason, it is not practical to create all possible thunks.
# Check that the BLR SLS hardening transforms BLRA* instructions into
# unconditional BL calls to the correct thunk functions.
# Check that only relevant thunk functions are generated.
--- |
define void @test_instructions() #0 {
entry:
ret void
}
define void @test_no_redef() #0 {
entry:
ret void
}
define void @test_regs() #0 {
entry:
ret void
}
attributes #0 = { "target-features"="+pauth,+harden-sls-blr" }
...
# Test that all BLRA* instructions are handled.
---
name: test_instructions
tracksRegLiveness: true
body: |
bb.0.entry:
liveins: $lr, $x0, $x1, $x2, $x3
BLRAA $x0, $x1, implicit-def $lr, implicit $sp, implicit-def $sp, implicit-def $w0
BLRAB $x1, $x2, implicit-def $lr, implicit $sp, implicit-def $sp, implicit-def $w0
BLRAAZ $x2, implicit-def $lr, implicit $sp, implicit-def $sp, implicit-def $w0
BLRABZ $x3, implicit-def $lr, implicit $sp, implicit-def $sp, implicit-def $w0
RET undef $lr
...
# Test that the same thunk function is not created twice.
---
name: test_no_redef
tracksRegLiveness: true
body: |
bb.0.entry:
liveins: $lr, $x0, $x1, $x2, $x3, $x4
; thunk used by @test_instructions
BLRAB $x1, $x2, implicit-def $lr, implicit $sp, implicit-def $sp, implicit-def $w0
; thunk used by this function twice
BLRAB $x3, $x4, implicit-def $lr, implicit $sp, implicit-def $sp, implicit-def $w0
BLRAB $x3, $x4, implicit-def $lr, implicit $sp, implicit-def $sp, implicit-def $w0
RET undef $lr
...
# Test that all xN registers (except x16, x17, x30 and xzr) are handled.
---
name: test_regs
tracksRegLiveness: true
body: |
bb.0.entry:
liveins: $lr, $x0, $x1, $x2, $x3, $x4, $x5, $x6, $x7, $x8, $x9, $x10, $x11, $x12, $x13, $x14, $x15, $x16, $x17, $x18, $x19, $x20, $x21, $x22, $x23, $x24, $x25, $x26, $x27, $x28, $fp
BLRAA $x0, $x1, implicit-def $lr, implicit $sp, implicit-def $sp, implicit-def $w0
BLRAA $x2, $x3, implicit-def $lr, implicit $sp, implicit-def $sp, implicit-def $w0
BLRAA $x4, $x5, implicit-def $lr, implicit $sp, implicit-def $sp, implicit-def $w0
BLRAA $x6, $x7, implicit-def $lr, implicit $sp, implicit-def $sp, implicit-def $w0
BLRAA $x8, $x9, implicit-def $lr, implicit $sp, implicit-def $sp, implicit-def $w0
BLRAA $x10, $x11, implicit-def $lr, implicit $sp, implicit-def $sp, implicit-def $w0
BLRAA $x12, $x13, implicit-def $lr, implicit $sp, implicit-def $sp, implicit-def $w0
BLRAA $x14, $x15, implicit-def $lr, implicit $sp, implicit-def $sp, implicit-def $w0
; skipping x16 and x17
BLRAA $x18, $x19, implicit-def $lr, implicit $sp, implicit-def $sp, implicit-def $w0
BLRAA $x20, $x21, implicit-def $lr, implicit $sp, implicit-def $sp, implicit-def $w0
BLRAA $x22, $x23, implicit-def $lr, implicit $sp, implicit-def $sp, implicit-def $w0
BLRAA $x24, $x25, implicit-def $lr, implicit $sp, implicit-def $sp, implicit-def $w0
BLRAA $x26, $x27, implicit-def $lr, implicit $sp, implicit-def $sp, implicit-def $w0
BLRAA $x28, $fp, implicit-def $lr, implicit $sp, implicit-def $sp, implicit-def $w0
RET undef $lr
...
# CHECK-LABEL: test_instructions:
# CHECK-NEXT: .cfi_startproc
# CHECK-NEXT: bl __llvm_slsblr_thunk_aa_x0_x1
# CHECK-NEXT: bl __llvm_slsblr_thunk_ab_x1_x2
# CHECK-NEXT: bl __llvm_slsblr_thunk_aaz_x2
# CHECK-NEXT: bl __llvm_slsblr_thunk_abz_x3
# CHECK-NEXT: ret
# CHECK-LABEL: test_no_redef:
# CHECK-NEXT: .cfi_startproc
# CHECK-NEXT: bl __llvm_slsblr_thunk_ab_x1_x2
# CHECK-NEXT: bl __llvm_slsblr_thunk_ab_x3_x4
# CHECK-NEXT: bl __llvm_slsblr_thunk_ab_x3_x4
# CHECK-NEXT: ret
# CHECK-LABEL: test_regs:
# CHECK-NEXT: .cfi_startproc
# CHECK-NEXT: bl __llvm_slsblr_thunk_aa_x0_x1
# CHECK-NEXT: bl __llvm_slsblr_thunk_aa_x2_x3
# CHECK-NEXT: bl __llvm_slsblr_thunk_aa_x4_x5
# CHECK-NEXT: bl __llvm_slsblr_thunk_aa_x6_x7
# CHECK-NEXT: bl __llvm_slsblr_thunk_aa_x8_x9
# CHECK-NEXT: bl __llvm_slsblr_thunk_aa_x10_x11
# CHECK-NEXT: bl __llvm_slsblr_thunk_aa_x12_x13
# CHECK-NEXT: bl __llvm_slsblr_thunk_aa_x14_x15
# skipping x16 and x17
# CHECK-NEXT: bl __llvm_slsblr_thunk_aa_x18_x19
# CHECK-NEXT: bl __llvm_slsblr_thunk_aa_x20_x21
# CHECK-NEXT: bl __llvm_slsblr_thunk_aa_x22_x23
# CHECK-NEXT: bl __llvm_slsblr_thunk_aa_x24_x25
# CHECK-NEXT: bl __llvm_slsblr_thunk_aa_x26_x27
# CHECK-NEXT: bl __llvm_slsblr_thunk_aa_x28_x29
# CHECK-NEXT: ret
# CHECK-LABEL: __llvm_slsblr_thunk_aa_x0_x1:
# CHECK-NEXT: mov x16, x0
# CHECK-NEXT: braa x16, x1
# CHECK-NEXT: dsb sy
# CHECK-NEXT: isb
# CHECK-LABEL: __llvm_slsblr_thunk_ab_x1_x2:
# CHECK-NEXT: mov x16, x1
# CHECK-NEXT: brab x16, x2
# CHECK-NEXT: dsb sy
# CHECK-NEXT: isb
# CHECK-LABEL: __llvm_slsblr_thunk_aaz_x2:
# CHECK-NEXT: mov x16, x2
# CHECK-NEXT: braaz x16
# CHECK-NEXT: dsb sy
# CHECK-NEXT: isb
# CHECK-LABEL: __llvm_slsblr_thunk_abz_x3:
# CHECK-NEXT: mov x16, x3
# CHECK-NEXT: brabz x16
# CHECK-NEXT: dsb sy
# CHECK-NEXT: isb
# The instruction *operands* should correspond to the thunk function *name*
# (check that the name is parsed correctly when populating the thunk).
# CHECK-LABEL: __llvm_slsblr_thunk_aa_x2_x3:
# CHECK-NEXT: mov x16, x2
# CHECK: braa x16, x3
# CHECK-LABEL: __llvm_slsblr_thunk_aa_x4_x5:
# CHECK-NEXT: mov x16, x4
# CHECK: braa x16, x5
# CHECK-LABEL: __llvm_slsblr_thunk_aa_x6_x7:
# CHECK-NEXT: mov x16, x6
# CHECK: braa x16, x7
# CHECK-LABEL: __llvm_slsblr_thunk_aa_x8_x9:
# CHECK-NEXT: mov x16, x8
# CHECK: braa x16, x9
# CHECK-LABEL: __llvm_slsblr_thunk_aa_x10_x11:
# CHECK-NEXT: mov x16, x10
# CHECK: braa x16, x11
# CHECK-LABEL: __llvm_slsblr_thunk_aa_x12_x13:
# CHECK-NEXT: mov x16, x12
# CHECK: braa x16, x13
# CHECK-LABEL: __llvm_slsblr_thunk_aa_x14_x15:
# CHECK-NEXT: mov x16, x14
# CHECK: braa x16, x15
# skipping x16 and x17
# CHECK-LABEL: __llvm_slsblr_thunk_aa_x18_x19:
# CHECK-NEXT: mov x16, x18
# CHECK: braa x16, x19
# CHECK-LABEL: __llvm_slsblr_thunk_aa_x20_x21:
# CHECK-NEXT: mov x16, x20
# CHECK: braa x16, x21
# CHECK-LABEL: __llvm_slsblr_thunk_aa_x22_x23:
# CHECK-NEXT: mov x16, x22
# CHECK: braa x16, x23
# CHECK-LABEL: __llvm_slsblr_thunk_aa_x24_x25:
# CHECK-NEXT: mov x16, x24
# CHECK: braa x16, x25
# CHECK-LABEL: __llvm_slsblr_thunk_aa_x26_x27:
# CHECK-NEXT: mov x16, x26
# CHECK: braa x16, x27
# CHECK-LABEL: __llvm_slsblr_thunk_aa_x28_x29:
# CHECK-NEXT: mov x16, x28
# CHECK: braa x16, x29
|
