Hexagon (target/hexagon) Change decision to set pkt_has_store_s[01]

We have found cases where pkt_has_store_s[01] is set incorrectly.
This leads to generating an unnecessary store that is left over
from a previous packet.

Add an attribute to determine if an instruction is a scalar store
The attribute is attached to the fSTORE macro (hex_common.py)
Update the logic in decode.c that sets pkt_has_store_s[01]

Signed-off-by: Taylor Simpson <tsimpson@quicinc.com>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Message-Id: <20220920080746.26791-4-tsimpson@quicinc.com>

target/hexagon/attribs_def.h.inc

@@ -44,6 +44,7 @@ DEF_ATTRIB(MEMSIZE_1B, "Memory width is 1 byte", "", "")
 DEF_ATTRIB(MEMSIZE_2B, "Memory width is 2 bytes", "", "")
 DEF_ATTRIB(MEMSIZE_4B, "Memory width is 4 bytes", "", "")
 DEF_ATTRIB(MEMSIZE_8B, "Memory width is 8 bytes", "", "")
+DEF_ATTRIB(SCALAR_STORE, "Store is scalar", "", "")
 DEF_ATTRIB(REGWRSIZE_1B, "Memory width is 1 byte", "", "")
 DEF_ATTRIB(REGWRSIZE_2B, "Memory width is 2 bytes", "", "")
 DEF_ATTRIB(REGWRSIZE_4B, "Memory width is 4 bytes", "", "")

target/hexagon/decode.c

@@ -1,5 +1,5 @@
 /*
- *  Copyright(c) 2019-2021 Qualcomm Innovation Center, Inc. All Rights Reserved.
+ *  Copyright(c) 2019-2022 Qualcomm Innovation Center, Inc. All Rights Reserved.
  *
  *  This program is free software; you can redistribute it and/or modify
  *  it under the terms of the GNU General Public License as published by
@@ -402,10 +402,13 @@ static void decode_set_insn_attr_fields(Packet *pkt)
         }
 
         if (GET_ATTRIB(opcode, A_STORE)) {
-            if (pkt->insn[i].slot == 0) {
-                pkt->pkt_has_store_s0 = true;
-            } else {
-                pkt->pkt_has_store_s1 = true;
+            if (GET_ATTRIB(opcode, A_SCALAR_STORE) &&
+                !GET_ATTRIB(opcode, A_MEMSIZE_0B)) {
+                if (pkt->insn[i].slot == 0) {
+                    pkt->pkt_has_store_s0 = true;
+                } else {
+                    pkt->pkt_has_store_s1 = true;
+                }
             }
         }
 

target/hexagon/hex_common.py

@@ -1,7 +1,7 @@
 #!/usr/bin/env python3
 
 ##
-##  Copyright(c) 2019-2021 Qualcomm Innovation Center, Inc. All Rights Reserved.
+##  Copyright(c) 2019-2022 Qualcomm Innovation Center, Inc. All Rights Reserved.
 ##
 ##  This program is free software; you can redistribute it and/or modify
 ##  it under the terms of the GNU General Public License as published by
@@ -75,6 +75,7 @@ def calculate_attribs():
     add_qemu_macro_attrib('fWRITE_P3', 'A_WRITES_PRED_REG')
     add_qemu_macro_attrib('fSET_OVERFLOW', 'A_IMPLICIT_WRITES_USR')
     add_qemu_macro_attrib('fSET_LPCFG', 'A_IMPLICIT_WRITES_USR')
+    add_qemu_macro_attrib('fSTORE', 'A_SCALAR_STORE')
 
     # Recurse down macros, find attributes from sub-macros
     macroValues = list(macros.values())

target/hexagon/translate.c

@@ -1,5 +1,5 @@
 /*
- *  Copyright(c) 2019-2021 Qualcomm Innovation Center, Inc. All Rights Reserved.
+ *  Copyright(c) 2019-2022 Qualcomm Innovation Center, Inc. All Rights Reserved.
  *
  *  This program is free software; you can redistribute it and/or modify
  *  it under the terms of the GNU General Public License as published by
@@ -499,10 +499,12 @@ static void process_store_log(DisasContext *ctx, Packet *pkt)
      *  slot 1 and then slot 0.  This will be important when
      *  the memory accesses overlap.
      */
-    if (pkt->pkt_has_store_s1 && !pkt->pkt_has_dczeroa) {
+    if (pkt->pkt_has_store_s1) {
+        g_assert(!pkt->pkt_has_dczeroa);
         process_store(ctx, pkt, 1);
     }
-    if (pkt->pkt_has_store_s0 && !pkt->pkt_has_dczeroa) {
+    if (pkt->pkt_has_store_s0) {
+        g_assert(!pkt->pkt_has_dczeroa);
         process_store(ctx, pkt, 0);
     }
 }
@@ -665,7 +667,7 @@ static void gen_commit_packet(CPUHexagonState *env, DisasContext *ctx,
          * The dczeroa will be the store in slot 0, check that we don't have
          * a store in slot 1 or an HVX store.
          */
-        g_assert(has_store_s0 && !has_store_s1 && !has_hvx_store);
+        g_assert(!has_store_s1 && !has_hvx_store);
         process_dczeroa(ctx, pkt);
     } else if (has_hvx_store) {
         TCGv mem_idx = tcg_constant_tl(ctx->mem_idx);