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-rw-r--r--disas/nanomips.cpp22
1 files changed, 22 insertions, 0 deletions
diff --git a/disas/nanomips.cpp b/disas/nanomips.cpp
index b0d0cf8901..c3b2bec943 100644
--- a/disas/nanomips.cpp
+++ b/disas/nanomips.cpp
@@ -468,6 +468,28 @@ uint64 NMD::decode_gpr_gpr4(uint64 d)
}
+/*
+ * NMD::decode_gpr_gpr2_reg1() - decoder for 'gpr2.reg1' gpr encoding type
+ *
+ * Map a 2-bit code to the 5-bit register space according to this pattern:
+ *
+ * 3 2 1 0
+ * | | | |
+ * | | | |
+ * | | | └-------------------┐
+ * | | └-------------------┐ |
+ * | └-------------------┐ | |
+ * └-------------------┐ | | |
+ * | | | |
+ * | | | |
+ * 1 0 9 8 7 6 5 4 3 2 1 0 9 8 7 6 5 4 3 2 1 0 9 8 7 6 5 4 3 2 1 0
+ * 3 2 1 0
+ *
+ * Used in handling following instructions:
+ *
+ * - MOVEP
+ * - MOVEP[REV]
+ */
uint64 NMD::decode_gpr_gpr2_reg1(uint64 d)
{
static uint64 register_list[] = { 4, 5, 6, 7 };