There is no need to use TESTL when checking the least-significant bit
with a TEST instruction. Use TESTB, which is three bytes shorter:
f6 05 00 00 00 00 01 testb $0x1,0x0(%rip)
vs:
f7 05 00 00 00 00 01 testl $0x1,0x0(%rip)
00 00 00
for the same effect.
No functional changes intended.
Signed-off-by: Uros Bizjak <ubizjak@gmail.com>
Signed-off-by: Borislav Petkov (AMD) <bp@alien8.de>
Link: https://lore.kernel.org/r/20231109201032.4439-1-ubizjak@gmail.com
/* Enable PAE mode, PSE, PGE and LA57 */
orl $(X86_CR4_PAE | X86_CR4_PSE | X86_CR4_PGE), %ecx
#ifdef CONFIG_X86_5LEVEL
- testl $1, __pgtable_l5_enabled(%rip)
+ testb $1, __pgtable_l5_enabled(%rip)
jz 1f
orl $X86_CR4_LA57, %ecx
1: