Christophe Leroy 19daf0aef8 powerpc/bpf/32: perform three operands ALU operations ...

When an ALU instruction is preceded by a MOV instruction
that just moves a source register into the destination register of
the ALU, replace that MOV+ALU instructions by an ALU operation
taking the source of the MOV as second source instead of using its
destination.

Before the change, code could look like the following, with
superfluous separate register move (mr) instructions.

  70:	7f c6 f3 78 	mr      r6,r30
  74:	7f a5 eb 78 	mr      r5,r29
  78:	30 c6 ff f4 	addic   r6,r6,-12
  7c:	7c a5 01 d4 	addme   r5,r5

With this commit, addition instructions take r30 and r29 directly.

  70:	30 de ff f4 	addic   r6,r30,-12
  74:	7c bd 01 d4 	addme   r5,r29

Signed-off-by: Christophe Leroy <christophe.leroy@csgroup.eu>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/b6719beaf01f9dcbcdbb787ef67c4a2f8e3a4cb6.1675245773.git.christophe.leroy@csgroup.eu

2023-02-10 22:17:35 +11:00

..

bpf_jit_comp32.c

powerpc/bpf/32: perform three operands ALU operations

2023-02-10 22:17:35 +11:00

bpf_jit_comp64.c

powerpc/bpf: Only pad length-variable code at initial pass

2023-02-10 22:17:35 +11:00

bpf_jit_comp.c

powerpc/bpf: Perform complete extra passes to update addresses

2023-02-10 22:17:35 +11:00

bpf_jit.h

powerpc/bpf: Perform complete extra passes to update addresses

2023-02-10 22:17:35 +11:00

Makefile

powerpc/bpf: Implement extended BPF on PPC32

2021-04-03 21:22:21 +11:00