[SRU][N:linux][PATCH v2 4/5] powerpc64/bpf: jit support for sign extended mov

[Andrei Gherzan]

BugLink: https://bugs.launchpad.net/bugs/2072994

Add jit support for sign extended mov. Tested using test_bpf module.

Signed-off-by: Artem Savkov <asavkov at redhat.com>
Signed-off-by: Michael Ellerman <mpe at ellerman.id.au>
Link: https://msgid.link/20240517075650.248801-5-asavkov@redhat.com
(cherry picked from commit 597b1710982d8ae61eb25c8084e3f8778b1a86b3)
Signed-off-by: Andrei Gherzan <andrei.gherzan at canonical.com>
---
 arch/powerpc/net/bpf_jit_comp64.c | 10 ++++++++--
 1 file changed, 8 insertions(+), 2 deletions(-)

diff --git a/arch/powerpc/net/bpf_jit_comp64.c b/arch/powerpc/net/bpf_jit_comp64.c
index ba67c9685761..240234b92a26 100644
--- a/arch/powerpc/net/bpf_jit_comp64.c
+++ b/arch/powerpc/net/bpf_jit_comp64.c
@@ -640,8 +640,14 @@ int bpf_jit_build_body(struct bpf_prog *fp, u32 *image, u32 *fimage, struct code
 				/* special mov32 for zext */
 				EMIT(PPC_RAW_RLWINM(dst_reg, dst_reg, 0, 0, 31));
 				break;
-			}
-			EMIT(PPC_RAW_MR(dst_reg, src_reg));
+			} else if (off == 8) {
+				EMIT(PPC_RAW_EXTSB(dst_reg, src_reg));
+			} else if (off == 16) {
+				EMIT(PPC_RAW_EXTSH(dst_reg, src_reg));
+			} else if (off == 32) {
+				EMIT(PPC_RAW_EXTSW(dst_reg, src_reg));
+			} else if (dst_reg != src_reg)
+				EMIT(PPC_RAW_MR(dst_reg, src_reg));
 			goto bpf_alu32_trunc;
 		case BPF_ALU | BPF_MOV | BPF_K: /* (u32) dst = imm */
 		case BPF_ALU64 | BPF_MOV | BPF_K: /* dst = (s64) imm */
-- 
2.43.0