[PATCHv2 3/7] ppc: bpf/jit: Optimize 64-bit Immediate loads

From: Naveen N. Rao
Date: Wed Jun 22 2016 - 12:28:48 EST


Similar to the LI32() optimization, if the value can be represented
in 32-bits, use LI32(). Also handle loading a few specific forms of
immediate values in an optimum manner.

Cc: Matt Evans <matt@xxxxxxxxxx>
Cc: Denis Kirjanov <kda@xxxxxxxxxxxxxxxxx>
Cc: Michael Ellerman <mpe@xxxxxxxxxxxxxx>
Cc: Paul Mackerras <paulus@xxxxxxxxx>
Cc: Alexei Starovoitov <ast@xxxxxx>
Cc: Daniel Borkmann <daniel@xxxxxxxxxxxxx>
Cc: "David S. Miller" <davem@xxxxxxxxxxxxx>
Cc: Ananth N Mavinakayanahalli <ananth@xxxxxxxxxx>
Cc: Thadeu Lima de Souza Cascardo <cascardo@xxxxxxxxxx>
Acked-by: Alexei Starovoitov <ast@xxxxxxxxxx>
Signed-off-by: Naveen N. Rao <naveen.n.rao@xxxxxxxxxxxxxxxxxx>
---
arch/powerpc/net/bpf_jit.h | 17 +++++++++++------
1 file changed, 11 insertions(+), 6 deletions(-)

diff --git a/arch/powerpc/net/bpf_jit.h b/arch/powerpc/net/bpf_jit.h
index a9882db..4c1e055 100644
--- a/arch/powerpc/net/bpf_jit.h
+++ b/arch/powerpc/net/bpf_jit.h
@@ -244,20 +244,25 @@ DECLARE_LOAD_FUNC(sk_load_byte_msh);
} } while(0)

#define PPC_LI64(d, i) do { \
- if (!((uintptr_t)(i) & 0xffffffff00000000ULL)) \
+ if ((long)(i) >= -2147483648 && \
+ (long)(i) < 2147483648) \
PPC_LI32(d, i); \
else { \
- PPC_LIS(d, ((uintptr_t)(i) >> 48)); \
- if ((uintptr_t)(i) & 0x0000ffff00000000ULL) \
- PPC_ORI(d, d, \
- ((uintptr_t)(i) >> 32) & 0xffff); \
+ if (!((uintptr_t)(i) & 0xffff800000000000ULL)) \
+ PPC_LI(d, ((uintptr_t)(i) >> 32) & 0xffff); \
+ else { \
+ PPC_LIS(d, ((uintptr_t)(i) >> 48)); \
+ if ((uintptr_t)(i) & 0x0000ffff00000000ULL) \
+ PPC_ORI(d, d, \
+ ((uintptr_t)(i) >> 32) & 0xffff); \
+ } \
PPC_SLDI(d, d, 32); \
if ((uintptr_t)(i) & 0x00000000ffff0000ULL) \
PPC_ORIS(d, d, \
((uintptr_t)(i) >> 16) & 0xffff); \
if ((uintptr_t)(i) & 0x000000000000ffffULL) \
PPC_ORI(d, d, (uintptr_t)(i) & 0xffff); \
- } } while (0);
+ } } while (0)

#ifdef CONFIG_PPC64
#define PPC_FUNC_ADDR(d,i) do { PPC_LI64(d, i); } while(0)
--
2.8.2