target/mips: Fix emulation of nanoMIPS MTHLIP instruction

The field ac in nanoMIPS instruction MTHLIP rs, ac is specified in
nanoMIPS documentation as opcode[15..14] (2 bits). However, in the
current QEMU code, the corresponding argument passed to the helper
gen_helper_mthlip() has the value of opcode[15..11] (5 bits). Right
shift the value of this argument by three bits to fix this.

Signed-off-by: Stefan Pejic <stefan.pejic@syrmia.com>
Reviewed-by: Philippe Mathieu-Daudé <f4bug@amsat.org>
Message-Id: <20220504110403.613168-2-stefan.pejic@syrmia.com>
Signed-off-by: Philippe Mathieu-Daudé <f4bug@amsat.org>

diff --git a/target/mips/tcg/nanomips_translate.c.inc b/target/mips/tcg/nanomips_translate.c.inc
index 916cece4d27e2a1a093d8ea861b7b01aa09e05b7..58ae35a1560af5d6ae552e352fef1041c450ead8 100644 (file)
--- a/target/mips/tcg/nanomips_translate.c.inc
+++ b/target/mips/tcg/nanomips_translate.c.inc
@@ -1597,7 +1597,7 @@ static void gen_pool32axf_1_nanomips_insn(DisasContext *ctx, uint32_t opc,
         check_dsp(ctx);
         switch (extract32(ctx->opcode, 12, 2)) {
         case NM_MTHLIP:
-            tcg_gen_movi_tl(t0, v2);
+            tcg_gen_movi_tl(t0, v2 >> 3);
             gen_helper_mthlip(t0, v0_t, cpu_env);
             break;
         case NM_SHILOV: