[PATCH 2/2] target/tricore: Fix OPC2_32_RRPW_EXTR for width=0

[Bastian Koppelmann <kbastian@mail.uni-paderborn.de>]

if width was 0 we would run into the assertion:

qemu-system-tricore: ../upstream/tcg/tcg-op.c:217: tcg_gen_sari_i32: Assertion `arg2 >= 0 && arg2 < 32' failed.o

The instruction manuel specifies undefined behaviour for this case. So
we bring this in line with the golden Infineon simlator 'tsim', which
simply writes 0 to the result in case of width=0.

Signed-off-by: Bastian Koppelmann <kbastian@mail.uni-paderborn.de>
---
 target/tricore/translate.c | 8 +++++++-
 1 file changed, 7 insertions(+), 1 deletion(-)

diff --git a/target/tricore/translate.c b/target/tricore/translate.c
index 67a7f646a2..d8b773ab37 100644
--- a/target/tricore/translate.c
+++ b/target/tricore/translate.c
@@ -6998,10 +6998,16 @@ static void decode_rrpw_extract_insert(DisasContext *ctx)
     pos = MASK_OP_RRPW_POS(ctx->opcode);
     width = MASK_OP_RRPW_WIDTH(ctx->opcode);
 
+
     switch (op2) {
     case OPC2_32_RRPW_EXTR:
+        if (width == 0) {
+                tcg_gen_movi_tl(cpu_gpr_d[r3], 0);
+                break;
+        }
+
         if (pos + width <= 32) {
-            /* optimize special cases */
+                        /* optimize special cases */
             if ((pos == 0) && (width == 8)) {
                 tcg_gen_ext8s_tl(cpu_gpr_d[r3], cpu_gpr_d[r1]);
             } else if ((pos == 0) && (width == 16)) {
-- 
2.30.1