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powerpc64/bpf: jit support for signed division and modulo

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Add jit support for sign division and modulo. Tested using test_bpf
module.

Signed-off-by: Artem Savkov <asavkov@redhat.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://msgid.link/20240517075650.248801-6-asavkov@redhat.com
This commit is contained in:
Artem Savkov 2024-05-17 09:56:50 +02:00 committed by Michael Ellerman
parent 597b171098
commit fde318326d
2 changed files with 34 additions and 8 deletions
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1
arch/powerpc/include/asm/ppc-opcode.h
View File

@ -536,6 +536,7 @@
#define PPC_RAW_MULI(d, a, i) (0x1c000000 | ___PPC_RT(d) | ___PPC_RA(a) | IMM_L(i))
#define PPC_RAW_DIVW(d, a, b) (0x7c0003d6 | ___PPC_RT(d) | ___PPC_RA(a) | ___PPC_RB(b))
#define PPC_RAW_DIVWU(d, a, b) (0x7c000396 | ___PPC_RT(d) | ___PPC_RA(a) | ___PPC_RB(b))
#define PPC_RAW_DIVD(d, a, b) (0x7c0003d2 | ___PPC_RT(d) | ___PPC_RA(a) | ___PPC_RB(b))
#define PPC_RAW_DIVDU(d, a, b) (0x7c000392 | ___PPC_RT(d) | ___PPC_RA(a) | ___PPC_RB(b))
#define PPC_RAW_DIVDE(t, a, b) (0x7c000352 | ___PPC_RT(t) | ___PPC_RA(a) | ___PPC_RB(b))
#define PPC_RAW_DIVDE_DOT(t, a, b) (0x7c000352 | ___PPC_RT(t) | ___PPC_RA(a) | ___PPC_RB(b) | 0x1)

25
arch/powerpc/net/bpf_jit_comp64.c
View File

@ -510,19 +510,32 @@ int bpf_jit_build_body(struct bpf_prog *fp, u32 *image, u32 *fimage, struct code
case BPF_ALU | BPF_DIV | BPF_X: /* (u32) dst /= (u32) src */
case BPF_ALU | BPF_MOD | BPF_X: /* (u32) dst %= (u32) src */
if (BPF_OP(code) == BPF_MOD) {
if (off)
EMIT(PPC_RAW_DIVW(tmp1_reg, dst_reg, src_reg));
else
EMIT(PPC_RAW_DIVWU(tmp1_reg, dst_reg, src_reg));
EMIT(PPC_RAW_MULW(tmp1_reg, src_reg, tmp1_reg));
EMIT(PPC_RAW_SUB(dst_reg, dst_reg, tmp1_reg));
} else
if (off)
EMIT(PPC_RAW_DIVW(dst_reg, dst_reg, src_reg));
else
EMIT(PPC_RAW_DIVWU(dst_reg, dst_reg, src_reg));
goto bpf_alu32_trunc;
case BPF_ALU64 | BPF_DIV | BPF_X: /* dst /= src */
case BPF_ALU64 | BPF_MOD | BPF_X: /* dst %= src */
if (BPF_OP(code) == BPF_MOD) {
if (off)
EMIT(PPC_RAW_DIVD(tmp1_reg, dst_reg, src_reg));
else
EMIT(PPC_RAW_DIVDU(tmp1_reg, dst_reg, src_reg));
EMIT(PPC_RAW_MULD(tmp1_reg, src_reg, tmp1_reg));
EMIT(PPC_RAW_SUB(dst_reg, dst_reg, tmp1_reg));
} else
if (off)
EMIT(PPC_RAW_DIVD(dst_reg, dst_reg, src_reg));
else
EMIT(PPC_RAW_DIVDU(dst_reg, dst_reg, src_reg));
break;
case BPF_ALU | BPF_MOD | BPF_K: /* (u32) dst %= (u32) imm */
@ -544,18 +557,30 @@ int bpf_jit_build_body(struct bpf_prog *fp, u32 *image, u32 *fimage, struct code
switch (BPF_CLASS(code)) {
case BPF_ALU:
if (BPF_OP(code) == BPF_MOD) {
if (off)
EMIT(PPC_RAW_DIVW(tmp2_reg, dst_reg, tmp1_reg));
else
EMIT(PPC_RAW_DIVWU(tmp2_reg, dst_reg, tmp1_reg));
EMIT(PPC_RAW_MULW(tmp1_reg, tmp1_reg, tmp2_reg));
EMIT(PPC_RAW_SUB(dst_reg, dst_reg, tmp1_reg));
} else
if (off)
EMIT(PPC_RAW_DIVW(dst_reg, dst_reg, tmp1_reg));
else
EMIT(PPC_RAW_DIVWU(dst_reg, dst_reg, tmp1_reg));
break;
case BPF_ALU64:
if (BPF_OP(code) == BPF_MOD) {
if (off)
EMIT(PPC_RAW_DIVD(tmp2_reg, dst_reg, tmp1_reg));
else
EMIT(PPC_RAW_DIVDU(tmp2_reg, dst_reg, tmp1_reg));
EMIT(PPC_RAW_MULD(tmp1_reg, tmp1_reg, tmp2_reg));
EMIT(PPC_RAW_SUB(dst_reg, dst_reg, tmp1_reg));
} else
if (off)
EMIT(PPC_RAW_DIVD(dst_reg, dst_reg, tmp1_reg));
else
EMIT(PPC_RAW_DIVDU(dst_reg, dst_reg, tmp1_reg));
break;
}