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Subject[PATCH 06/13] x86/crypto/crc32c-pcl-intel: Standardize jump table
Date
Simplify the jump table code so that it resembles a compiler-generated
table.

This enables ORC unwinding by allowing objtool to follow all the
potential code paths.

Signed-off-by: Josh Poimboeuf <jpoimboe@redhat.com>
---
arch/x86/crypto/crc32c-pcl-intel-asm_64.S | 7 ++-----
1 file changed, 2 insertions(+), 5 deletions(-)

diff --git a/arch/x86/crypto/crc32c-pcl-intel-asm_64.S b/arch/x86/crypto/crc32c-pcl-intel-asm_64.S
index 884dc767b051..ac1f303eed0f 100644
--- a/arch/x86/crypto/crc32c-pcl-intel-asm_64.S
+++ b/arch/x86/crypto/crc32c-pcl-intel-asm_64.S
@@ -53,7 +53,7 @@
.endm

.macro JMPTBL_ENTRY i
-.word crc_\i - crc_array
+.quad crc_\i
.endm

.macro JNC_LESS_THAN j
@@ -168,10 +168,7 @@ continue_block:
xor crc2, crc2

## branch into array
- lea jump_table(%rip), %bufp
- movzwq (%bufp, %rax, 2), len
- lea crc_array(%rip), %bufp
- lea (%bufp, len, 1), %bufp
+ mov jump_table(,%rax,8), %bufp
JMP_NOSPEC bufp

################################################################
--
2.29.2
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