powerpc: bpf: eliminate zero extension code-gen

Cc: Naveen N. Rao <naveen.n.rao@linux.ibm.com>
Cc: Sandipan Das <sandipan@linux.ibm.com>
Signed-off-by: Jiong Wang <jiong.wang@netronome.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
This commit is contained in:
Jiong Wang 2019-05-24 23:25:23 +01:00 committed by Alexei Starovoitov
parent 163541e6ba
commit a4c927733e

View File

@ -504,6 +504,9 @@ static int bpf_jit_build_body(struct bpf_prog *fp, u32 *image,
case BPF_ALU | BPF_LSH | BPF_X: /* (u32) dst <<= (u32) src */
/* slw clears top 32 bits */
PPC_SLW(dst_reg, dst_reg, src_reg);
/* skip zero extension move, but set address map. */
if (insn_is_zext(&insn[i + 1]))
addrs[++i] = ctx->idx * 4;
break;
case BPF_ALU64 | BPF_LSH | BPF_X: /* dst <<= src; */
PPC_SLD(dst_reg, dst_reg, src_reg);
@ -511,6 +514,8 @@ static int bpf_jit_build_body(struct bpf_prog *fp, u32 *image,
case BPF_ALU | BPF_LSH | BPF_K: /* (u32) dst <<== (u32) imm */
/* with imm 0, we still need to clear top 32 bits */
PPC_SLWI(dst_reg, dst_reg, imm);
if (insn_is_zext(&insn[i + 1]))
addrs[++i] = ctx->idx * 4;
break;
case BPF_ALU64 | BPF_LSH | BPF_K: /* dst <<== imm */
if (imm != 0)
@ -518,12 +523,16 @@ static int bpf_jit_build_body(struct bpf_prog *fp, u32 *image,
break;
case BPF_ALU | BPF_RSH | BPF_X: /* (u32) dst >>= (u32) src */
PPC_SRW(dst_reg, dst_reg, src_reg);
if (insn_is_zext(&insn[i + 1]))
addrs[++i] = ctx->idx * 4;
break;
case BPF_ALU64 | BPF_RSH | BPF_X: /* dst >>= src */
PPC_SRD(dst_reg, dst_reg, src_reg);
break;
case BPF_ALU | BPF_RSH | BPF_K: /* (u32) dst >>= (u32) imm */
PPC_SRWI(dst_reg, dst_reg, imm);
if (insn_is_zext(&insn[i + 1]))
addrs[++i] = ctx->idx * 4;
break;
case BPF_ALU64 | BPF_RSH | BPF_K: /* dst >>= imm */
if (imm != 0)
@ -548,6 +557,11 @@ static int bpf_jit_build_body(struct bpf_prog *fp, u32 *image,
*/
case BPF_ALU | BPF_MOV | BPF_X: /* (u32) dst = src */
case BPF_ALU64 | BPF_MOV | BPF_X: /* dst = src */
if (imm == 1) {
/* special mov32 for zext */
PPC_RLWINM(dst_reg, dst_reg, 0, 0, 31);
break;
}
PPC_MR(dst_reg, src_reg);
goto bpf_alu32_trunc;
case BPF_ALU | BPF_MOV | BPF_K: /* (u32) dst = imm */
@ -555,11 +569,13 @@ static int bpf_jit_build_body(struct bpf_prog *fp, u32 *image,
PPC_LI32(dst_reg, imm);
if (imm < 0)
goto bpf_alu32_trunc;
else if (insn_is_zext(&insn[i + 1]))
addrs[++i] = ctx->idx * 4;
break;
bpf_alu32_trunc:
/* Truncate to 32-bits */
if (BPF_CLASS(code) == BPF_ALU)
if (BPF_CLASS(code) == BPF_ALU && !fp->aux->verifier_zext)
PPC_RLWINM(dst_reg, dst_reg, 0, 0, 31);
break;
@ -618,10 +634,13 @@ emit_clear:
case 16:
/* zero-extend 16 bits into 64 bits */
PPC_RLDICL(dst_reg, dst_reg, 0, 48);
if (insn_is_zext(&insn[i + 1]))
addrs[++i] = ctx->idx * 4;
break;
case 32:
/* zero-extend 32 bits into 64 bits */
PPC_RLDICL(dst_reg, dst_reg, 0, 32);
if (!fp->aux->verifier_zext)
/* zero-extend 32 bits into 64 bits */
PPC_RLDICL(dst_reg, dst_reg, 0, 32);
break;
case 64:
/* nop */
@ -698,14 +717,20 @@ emit_clear:
/* dst = *(u8 *)(ul) (src + off) */
case BPF_LDX | BPF_MEM | BPF_B:
PPC_LBZ(dst_reg, src_reg, off);
if (insn_is_zext(&insn[i + 1]))
addrs[++i] = ctx->idx * 4;
break;
/* dst = *(u16 *)(ul) (src + off) */
case BPF_LDX | BPF_MEM | BPF_H:
PPC_LHZ(dst_reg, src_reg, off);
if (insn_is_zext(&insn[i + 1]))
addrs[++i] = ctx->idx * 4;
break;
/* dst = *(u32 *)(ul) (src + off) */
case BPF_LDX | BPF_MEM | BPF_W:
PPC_LWZ(dst_reg, src_reg, off);
if (insn_is_zext(&insn[i + 1]))
addrs[++i] = ctx->idx * 4;
break;
/* dst = *(u64 *)(ul) (src + off) */
case BPF_LDX | BPF_MEM | BPF_DW:
@ -1046,6 +1071,11 @@ struct powerpc64_jit_data {
struct codegen_context ctx;
};
bool bpf_jit_needs_zext(void)
{
return true;
}
struct bpf_prog *bpf_int_jit_compile(struct bpf_prog *fp)
{
u32 proglen;