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[BOLT][Linux] Fix static keys test case (#119771)

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The key address in the static keys jump table was incorrectly encoded as
an absolute value instead of PC-relative causing incorrect
interpretation of the "likely" property of the key.
This commit is contained in:
Maksim Panchenko
2024-12-15 17:13:04 -08:00
committed by GitHub
parent 8daf4f16fa
commit f86f4574bb
1 changed files with 15 additions and 9 deletions
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24
bolt/test/X86/linux-static-keys.s
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@@ -35,13 +35,13 @@ _start:
.L0:
jmp L1
# CHECK: jit
# CHECK-SAME: # ID: 1 {{.*}} # Likely: 0 # InitValue: 1
# CHECK-SAME: # ID: 1 {{.*}} # Likely: 1 # InitValue: 0
nop
L1:
.nops 5
jmp .L0
# CHECK: jit
# CHECK-SAME: # ID: 2 {{.*}} # Likely: 1 # InitValue: 1
# CHECK-SAME: # ID: 2 {{.*}} # Likely: 0 # InitValue: 0
jmp .L0
## Check that a branch profile associated with a NOP is handled properly when
## dynamic branch is created.
@@ -67,18 +67,24 @@ foo:
.type __start___jump_table, %object
__start___jump_table:
.long .L0 - . # Jump address
.long L1 - . # Target address
.quad 1 # Key address
.long .L0 - . # Jump address
.long L1 - . # Target address
.quad fake_static_key + 1 - . # Key address; LSB = 1 : likely
.long L1 - . # Jump address
.long L2 - . # Target address
.quad 0 # Key address
.long L1 - . # Jump address
.long L2 - . # Target address
.quad fake_static_key -. # Key address; LSB = 0 : unlikely
.globl __stop___jump_table
.type __stop___jump_table, %object
__stop___jump_table:
## Staic keys (we just use the label ignoring the format of the keys).
.data
.align 8
fake_static_key:
.quad 0
## Fake Linux Kernel sections.
.section __ksymtab,"a",@progbits
.section __ksymtab_gpl,"a",@progbits