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riscv, bpf: Unify 32-bit sign-extension to emit_sextw

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For code unification, add emit_sextw wrapper to unify all the 32-bit
sign-extension operations.

Signed-off-by: Pu Lehui <pulehui@huawei.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Tested-by: Björn Töpel <bjorn@rivosinc.com>
Acked-by: Björn Töpel <bjorn@kernel.org>
Link: https://lore.kernel.org/bpf/20240115131235.2914289-2-pulehui@huaweicloud.com
This commit is contained in:
Pu Lehui 2024-01-15 13:12:30 +00:00 committed by Daniel Borkmann
parent ad57654053
commit e33758f749
2 changed files with 10 additions and 5 deletions
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5
arch/riscv/net/bpf_jit.h
View File

@ -1087,6 +1087,11 @@ static inline void emit_subw(u8 rd, u8 rs1, u8 rs2, struct rv_jit_context *ctx)
emit(rv_subw(rd, rs1, rs2), ctx);
}
static inline void emit_sextw(u8 rd, u8 rs, struct rv_jit_context *ctx)
{
emit_addiw(rd, rs, 0, ctx);
}
#endif /* __riscv_xlen == 64 */
void bpf_jit_build_prologue(struct rv_jit_context *ctx);

10
arch/riscv/net/bpf_jit_comp64.c
View File

@ -417,8 +417,8 @@ static void emit_zext_32_rd_rs(u8 *rd, u8 *rs, struct rv_jit_context *ctx)
static void emit_sext_32_rd_rs(u8 *rd, u8 *rs, struct rv_jit_context *ctx)
{
emit_addiw(RV_REG_T2, *rd, 0, ctx);
emit_addiw(RV_REG_T1, *rs, 0, ctx);
emit_sextw(RV_REG_T2, *rd, ctx);
emit_sextw(RV_REG_T1, *rs, ctx);
*rd = RV_REG_T2;
*rs = RV_REG_T1;
}
@ -433,7 +433,7 @@ static void emit_zext_32_rd_t1(u8 *rd, struct rv_jit_context *ctx)
static void emit_sext_32_rd(u8 *rd, struct rv_jit_context *ctx)
{
emit_addiw(RV_REG_T2, *rd, 0, ctx);
emit_sextw(RV_REG_T2, *rd, ctx);
*rd = RV_REG_T2;
}
@ -1104,7 +1104,7 @@ int bpf_jit_emit_insn(const struct bpf_insn *insn, struct rv_jit_context *ctx,
emit_srai(rd, RV_REG_T1, 64 - insn->off, ctx);
break;
case 32:
emit_addiw(rd, rs, 0, ctx);
emit_sextw(rd, rs, ctx);
break;
}
if (!is64 && !aux->verifier_zext)
@ -1504,7 +1504,7 @@ out_be:
* as t1 is used only in comparison against zero.
*/
if (!is64 && imm < 0)
emit_addiw(RV_REG_T1, RV_REG_T1, 0, ctx);
emit_sextw(RV_REG_T1, RV_REG_T1, ctx);
e = ctx->ninsns;
rvoff -= ninsns_rvoff(e - s);
emit_branch(BPF_JNE, RV_REG_T1, RV_REG_ZERO, rvoff, ctx);