From 3e2a33cf7e68b95c3afe11e967769341f6dc987d Mon Sep 17 00:00:00 2001 From: Jiong Wang Date: Fri, 24 May 2019 23:25:25 +0100 Subject: [PATCH] sparc: bpf: eliminate zero extension code-gen Cc: David S. Miller Signed-off-by: Jiong Wang Signed-off-by: Alexei Starovoitov --- arch/sparc/net/bpf_jit_comp_64.c | 29 +++++++++++++++++++++++++++-- 1 file changed, 27 insertions(+), 2 deletions(-) diff --git a/arch/sparc/net/bpf_jit_comp_64.c b/arch/sparc/net/bpf_jit_comp_64.c index 65428e79b2f3..3364e2a00989 100644 --- a/arch/sparc/net/bpf_jit_comp_64.c +++ b/arch/sparc/net/bpf_jit_comp_64.c @@ -908,6 +908,8 @@ static int build_insn(const struct bpf_insn *insn, struct jit_ctx *ctx) /* dst = src */ case BPF_ALU | BPF_MOV | BPF_X: emit_alu3_K(SRL, src, 0, dst, ctx); + if (insn_is_zext(&insn[1])) + return 1; break; case BPF_ALU64 | BPF_MOV | BPF_X: emit_reg_move(src, dst, ctx); @@ -942,6 +944,8 @@ static int build_insn(const struct bpf_insn *insn, struct jit_ctx *ctx) case BPF_ALU | BPF_DIV | BPF_X: emit_write_y(G0, ctx); emit_alu(DIV, src, dst, ctx); + if (insn_is_zext(&insn[1])) + return 1; break; case BPF_ALU64 | BPF_DIV | BPF_X: emit_alu(UDIVX, src, dst, ctx); @@ -975,6 +979,8 @@ static int build_insn(const struct bpf_insn *insn, struct jit_ctx *ctx) break; case BPF_ALU | BPF_RSH | BPF_X: emit_alu(SRL, src, dst, ctx); + if (insn_is_zext(&insn[1])) + return 1; break; case BPF_ALU64 | BPF_RSH | BPF_X: emit_alu(SRLX, src, dst, ctx); @@ -997,9 +1003,12 @@ static int build_insn(const struct bpf_insn *insn, struct jit_ctx *ctx) case 16: emit_alu_K(SLL, dst, 16, ctx); emit_alu_K(SRL, dst, 16, ctx); + if (insn_is_zext(&insn[1])) + return 1; break; case 32: - emit_alu_K(SRL, dst, 0, ctx); + if (!ctx->prog->aux->verifier_zext) + emit_alu_K(SRL, dst, 0, ctx); break; case 64: /* nop */ @@ -1021,6 +1030,8 @@ static int build_insn(const struct bpf_insn *insn, struct jit_ctx *ctx) emit_alu3_K(AND, dst, 0xff, dst, ctx); emit_alu3_K(SLL, tmp, 8, tmp, ctx); emit_alu(OR, tmp, dst, ctx); + if (insn_is_zext(&insn[1])) + return 1; break; case 32: @@ -1037,6 +1048,8 @@ static int build_insn(const struct bpf_insn *insn, struct jit_ctx *ctx) emit_alu3_K(AND, dst, 0xff, dst, ctx); /* dst = dst & 0xff */ emit_alu3_K(SLL, dst, 24, dst, ctx); /* dst = dst << 24 */ emit_alu(OR, tmp, dst, ctx); /* dst = dst | tmp */ + if (insn_is_zext(&insn[1])) + return 1; break; case 64: @@ -1050,6 +1063,8 @@ static int build_insn(const struct bpf_insn *insn, struct jit_ctx *ctx) /* dst = imm */ case BPF_ALU | BPF_MOV | BPF_K: emit_loadimm32(imm, dst, ctx); + if (insn_is_zext(&insn[1])) + return 1; break; case BPF_ALU64 | BPF_MOV | BPF_K: emit_loadimm_sext(imm, dst, ctx); @@ -1132,6 +1147,8 @@ static int build_insn(const struct bpf_insn *insn, struct jit_ctx *ctx) break; case BPF_ALU | BPF_RSH | BPF_K: emit_alu_K(SRL, dst, imm, ctx); + if (insn_is_zext(&insn[1])) + return 1; break; case BPF_ALU64 | BPF_RSH | BPF_K: emit_alu_K(SRLX, dst, imm, ctx); @@ -1144,7 +1161,8 @@ static int build_insn(const struct bpf_insn *insn, struct jit_ctx *ctx) break; do_alu32_trunc: - if (BPF_CLASS(code) == BPF_ALU) + if (BPF_CLASS(code) == BPF_ALU && + !ctx->prog->aux->verifier_zext) emit_alu_K(SRL, dst, 0, ctx); break; @@ -1265,6 +1283,8 @@ static int build_insn(const struct bpf_insn *insn, struct jit_ctx *ctx) rs2 = RS2(tmp); } emit(opcode | RS1(src) | rs2 | RD(dst), ctx); + if (opcode != LD64 && insn_is_zext(&insn[1])) + return 1; break; } /* ST: *(size *)(dst + off) = imm */ @@ -1432,6 +1452,11 @@ static void jit_fill_hole(void *area, unsigned int size) *ptr++ = 0x91d02005; /* ta 5 */ } +bool bpf_jit_needs_zext(void) +{ + return true; +} + struct sparc64_jit_data { struct bpf_binary_header *header; u8 *image;