[PATCH bpf-next v2 3/7] riscv, bpf: Support sign-extension mov insns

[Pu Lehui]

From: Pu Lehui <pulehui at huawei.com>

Add support sign-extension mov instructions for RV64.

Signed-off-by: Pu Lehui <pulehui at huawei.com>
---
 arch/riscv/net/bpf_jit_comp64.c | 14 +++++++++++++-
 1 file changed, 13 insertions(+), 1 deletion(-)

diff --git a/arch/riscv/net/bpf_jit_comp64.c b/arch/riscv/net/bpf_jit_comp64.c
index fd36cb17101a..bcf1e7509cb9 100644
--- a/arch/riscv/net/bpf_jit_comp64.c
+++ b/arch/riscv/net/bpf_jit_comp64.c
@@ -1047,7 +1047,19 @@ int bpf_jit_emit_insn(const struct bpf_insn *insn, struct rv_jit_context *ctx,
 			emit_zext_32(rd, ctx);
 			break;
 		}
-		emit_mv(rd, rs, ctx);
+		switch (insn->off) {
+		case 0:
+			emit_mv(rd, rs, ctx);
+			break;
+		case 8:
+		case 16:
+			emit_slli(RV_REG_T1, rs, 64 - insn->off, ctx);
+			emit_srai(rd, RV_REG_T1, 64 - insn->off, ctx);
+			break;
+		case 32:
+			emit_addiw(rd, rs, 0, ctx);
+			break;
+		}
 		if (!is64 && !aux->verifier_zext)
 			emit_zext_32(rd, ctx);
 		break;
-- 
2.39.2