From 5312546b4fd0c2dbca7dd7b4a2a4e865de2e418d Mon Sep 17 00:00:00 2001
From: Brian Cain <bcain@quicinc.com>
Date: Mon, 22 Jun 2026 15:28:46 -0700
Subject: [PATCH] target/hexagon: Add pkt_ends_tb to translation

Reviewed-by: Taylor Simpson <ltaylorsimpson@gmail.com>
Signed-off-by: Brian Cain <brian.cain@oss.qualcomm.com>
---
 target/hexagon/translate.c | 102 ++++++++++++++++++++++++++++++++++++-
 target/hexagon/translate.h |   1 -
 2 files changed, 100 insertions(+), 3 deletions(-)

diff --git a/target/hexagon/translate.c b/target/hexagon/translate.c
index ce5bbe92d5..35e9036288 100644
--- a/target/hexagon/translate.c
+++ b/target/hexagon/translate.c
@@ -270,6 +270,16 @@ static bool check_for_attrib(Packet *pkt, int attrib)
     return false;
 }
 
+static bool check_for_opcode(Packet *pkt, uint16_t opcode)
+{
+    for (int i = 0; i < pkt->num_insns; i++) {
+        if (pkt->insn[i].opcode == opcode) {
+            return true;
+        }
+    }
+    return false;
+}
+
 static bool need_slot_cancelled(Packet *pkt)
 {
     /* We only need slot_cancelled for conditional store instructions */
@@ -283,6 +293,90 @@ static bool need_slot_cancelled(Packet *pkt)
     return false;
 }
 
+#ifndef CONFIG_USER_ONLY
+static bool sreg_write_ends_tb(int reg_num)
+{
+    return reg_num == HEX_SREG_SSR ||
+           reg_num == HEX_SREG_STID ||
+           reg_num == HEX_SREG_IMASK ||
+           reg_num == HEX_SREG_IPENDAD ||
+           reg_num == HEX_SREG_BESTWAIT ||
+           reg_num == HEX_SREG_SCHEDCFG;
+}
+
+static bool has_sreg_write_ends_tb(Packet const *pkt)
+{
+    for (int i = 0; i < pkt->num_insns; i++) {
+        Insn const *insn = &pkt->insn[i];
+        uint16_t opcode = insn->opcode;
+        if (opcode == Y2_tfrsrcr) {
+            /* Write to a single sreg */
+            int reg_num = insn->regno[0];
+            if (sreg_write_ends_tb(reg_num)) {
+                return true;
+            }
+        } else if (opcode == Y4_tfrspcp) {
+            /* Write to a sreg pair */
+            int reg_num = insn->regno[0];
+            if (sreg_write_ends_tb(reg_num)) {
+                return true;
+            }
+            if (sreg_write_ends_tb(reg_num + 1)) {
+                return true;
+            }
+        }
+    }
+    return false;
+}
+#endif
+
+static bool pkt_ends_tb(Packet *pkt)
+{
+    if (pkt->pkt_has_cof) {
+        return true;
+    }
+#ifndef CONFIG_USER_ONLY
+    /* System mode instructions that end TLB */
+    if (check_for_opcode(pkt, Y2_swi) ||
+        check_for_opcode(pkt, Y2_cswi) ||
+        check_for_opcode(pkt, Y2_ciad) ||
+        check_for_opcode(pkt, Y4_siad) ||
+        check_for_opcode(pkt, Y2_wait) ||
+        check_for_opcode(pkt, Y2_resume) ||
+        check_for_opcode(pkt, Y2_iassignw) ||
+        check_for_opcode(pkt, Y2_setimask) ||
+        check_for_opcode(pkt, Y4_nmi) ||
+        check_for_opcode(pkt, Y2_setprio) ||
+        check_for_opcode(pkt, Y2_start) ||
+        check_for_opcode(pkt, Y2_stop) ||
+        check_for_opcode(pkt, Y2_k0lock) ||
+        check_for_opcode(pkt, Y2_k0unlock) ||
+        check_for_opcode(pkt, Y2_tlblock) ||
+        check_for_opcode(pkt, Y2_tlbunlock) ||
+        check_for_opcode(pkt, Y2_break) ||
+        check_for_opcode(pkt, Y2_isync) ||
+        check_for_opcode(pkt, Y2_syncht) ||
+        check_for_opcode(pkt, Y2_tlbp) ||
+        check_for_opcode(pkt, Y2_tlbw) ||
+        check_for_opcode(pkt, Y5_ctlbw) ||
+        check_for_opcode(pkt, Y5_tlbasidi)) {
+        return true;
+    }
+
+    /*
+     * Check for sreg writes that would end the TB
+     */
+    if (check_for_attrib(pkt, A_IMPLICIT_WRITES_SSR)) {
+        return true;
+    }
+    if (has_sreg_write_ends_tb(pkt)) {
+        return true;
+    }
+#endif
+    return false;
+}
+
+
 static bool need_next_PC(DisasContext *ctx)
 {
     /* Check for conditional control flow or HW loop end */
@@ -439,7 +533,11 @@ static void analyze_packet(DisasContext *ctx)
 
 static void gen_start_packet(DisasContext *ctx)
 {
-    target_ulong next_PC = ctx->base.pc_next + ctx->pkt.encod_pkt_size_in_bytes;
+    Packet *pkt = &ctx->pkt;
+    target_ulong next_PC = (check_for_opcode(pkt, Y2_k0lock) ||
+                            check_for_opcode(pkt, Y2_tlblock)) ?
+                               ctx->base.pc_next :
+                               ctx->base.pc_next + pkt->encod_pkt_size_in_bytes;
     int i;
 
     /* Clear out the disassembly context */
@@ -944,7 +1042,7 @@ static void gen_commit_packet(DisasContext *ctx)
         ctx->pkt.vhist_insn->generate(ctx);
     }
 
-    if (ctx->pkt.pkt_has_cof) {
+    if (pkt_ends_tb(&ctx->pkt) || ctx->base.is_jmp == DISAS_NORETURN) {
         gen_end_tb(ctx);
     }
 }
diff --git a/target/hexagon/translate.h b/target/hexagon/translate.h
index f79bdedd7b..fea88cb2db 100644
--- a/target/hexagon/translate.h
+++ b/target/hexagon/translate.h
@@ -86,7 +86,6 @@ typedef struct DisasContext {
     TCGv branch_taken;
     TCGv dczero_addr;
     bool pcycle_enabled;
-    bool pkt_ends_tb;
     uint32_t num_cycles;
 } DisasContext;