On 5/20/26 03:41, Philippe Mathieu-Daudé wrote:
On 20/5/26 12:18, Philippe Mathieu-Daudé wrote:
From: James Hilliard <[email protected]>
Add the MTP0, MTP1, and MTP2 forms. MTP0 loads the low Octeon3
partial-product pair from rs/rt into P[0]/P[3], MTP1 loads the middle
pair into P[1]/P[4], and MTP2 loads the high pair into P[2]/P[5].
For MTP0, also set P[1] to zero for backward compatibility with
Octeon2 VMULU.
Legacy single-source encodings have rt encoded as $zero, so the same
translator path also preserves the older Octeon behavior.
Reviewed-by: Richard Henderson <[email protected]>
Signed-off-by: James Hilliard <[email protected]>
Signed-off-by: Richard Henderson <[email protected]>
Signed-off-by: Philippe Mathieu-Daudé <[email protected]>
---
target/mips/tcg/octeon.decode | 4 ++++
target/mips/tcg/octeon_translate.c | 23 +++++++++++++++++++++++
2 files changed, 27 insertions(+)
diff --git a/target/mips/tcg/octeon.decode b/target/mips/tcg/octeon.decode
index 5139543b153..bb0a9f1d99a 100644
--- a/target/mips/tcg/octeon.decode
+++ b/target/mips/tcg/octeon.decode
@@ -51,6 +51,10 @@ MTM0 011100 ..... ..... 00000 00000 001000 @r2
MTM1 011100 ..... ..... 00000 00000 001100 @r2
MTM2 011100 ..... ..... 00000 00000 001101 @r2
+MTP0 011100 ..... ..... 00000 00000 001001 @r2
+MTP1 011100 ..... ..... 00000 00000 001010 @r2
+MTP2 011100 ..... ..... 00000 00000 001011 @r2
+
&saa base rt
@saa ...... base:5 rt:5 ................ &saa
SAA 011100 ..... ..... 00000 00000 011000 @saa
diff --git a/target/mips/tcg/octeon_translate.c
b/target/mips/tcg/octeon_translate.c
index aae6e9811c8..36d268e09c4 100644
--- a/target/mips/tcg/octeon_translate.c
+++ b/target/mips/tcg/octeon_translate.c
@@ -242,3 +242,26 @@ static bool trans_mtm(DisasContext *ctx, arg_r2 *a, unsigned int
index)
TRANS(MTM0, trans_mtm, 0);
TRANS(MTM1, trans_mtm, 1);
TRANS(MTM2, trans_mtm, 2);
+
+static bool trans_mtp(DisasContext *ctx, arg_r2 *a, unsigned int index)
+{
+ /*
+ * Octeon3 two-source MTP forms load lane index from rs and lane index + 3
+ * from rt. Legacy one-source forms encode rt as $zero.
+ */
+ gen_load_gpr(oct_p[index], a->rs);
+ gen_load_gpr(oct_p[index + 3], a->rt);
+
+ /*
+ * Octeon3 clears P1 with P0 so that VMULU sequences remain
I think you meant s/P0/$0/ here. Otherwise:
No. MTP0 writes P0 and clears P1.
Perhaps better as "...clears P1 with a write to P0..."
r~
