[PATCH 4/8] Hexagon (target/hexagon) Add overrides for direct call instructions

[Taylor Simpson]

Add overrides for
    J2_call
    J2_callt
    J2_callf

Signed-off-by: Taylor Simpson <tsimpson@quicinc.com>
---
 target/hexagon/gen_tcg.h |  8 ++++++
 target/hexagon/genptr.c  | 59 ++++++++++++++++++++++++++++++++++++++++
 2 files changed, 67 insertions(+)

diff --git a/target/hexagon/gen_tcg.h b/target/hexagon/gen_tcg.h
index e6fc7d97d2..ad149adbe1 100644
--- a/target/hexagon/gen_tcg.h
+++ b/target/hexagon/gen_tcg.h
@@ -612,6 +612,14 @@
         tcg_temp_free(tmp); \
     } while (0)
 
+#define fGEN_TCG_J2_call(SHORTCODE) \
+    gen_call(ctx, pkt, riV)
+
+#define fGEN_TCG_J2_callt(SHORTCODE) \
+    gen_cond_call(ctx, pkt, PuV, true, riV)
+#define fGEN_TCG_J2_callf(SHORTCODE) \
+    gen_cond_call(ctx, pkt, PuV, false, riV)
+
 #define fGEN_TCG_J2_pause(SHORTCODE) \
     do { \
         uiV = uiV; \
diff --git a/target/hexagon/genptr.c b/target/hexagon/genptr.c
index 806d0974ff..4b43b3f5c8 100644
--- a/target/hexagon/genptr.c
+++ b/target/hexagon/genptr.c
@@ -456,6 +456,65 @@ static TCGv gen_8bitsof(TCGv result, TCGv value)
     return result;
 }
 
+static void gen_write_new_pc_pcrel(DisasContext *ctx, Packet *pkt,
+                                   int pc_off, TCGv pred)
+{
+    target_ulong dest = pkt->pc + pc_off;
+    if (pkt->pkt_has_multi_cof) {
+        TCGLabel *pred_false = NULL;
+        if (pred != NULL) {
+            pred_false = gen_new_label();
+            tcg_gen_brcondi_tl(TCG_COND_EQ, pred, 0, pred_false);
+        }
+        /* If there are multiple branches in a packet, ignore the second one */
+        TCGLabel *skip = gen_new_label();
+        tcg_gen_brcondi_tl(TCG_COND_NE, hex_branch_taken, 0, skip);
+        tcg_gen_movi_tl(hex_gpr[HEX_REG_PC], dest);
+        tcg_gen_movi_tl(hex_branch_taken, 1);
+        gen_set_label(skip);
+        if (pred != NULL) {
+            gen_set_label(pred_false);
+        }
+    } else {
+        TCGLabel *pred_false = NULL;
+        if (pred != NULL) {
+            pred_false = gen_new_label();
+            tcg_gen_brcondi_tl(TCG_COND_EQ, pred, 0, pred_false);
+        }
+        tcg_gen_movi_tl(hex_gpr[HEX_REG_PC], dest);
+        if (pred != NULL) {
+            gen_set_label(pred_false);
+        }
+    }
+}
+
+static void gen_call(DisasContext *ctx, Packet *pkt, int pc_off)
+{
+    TCGv next_PC =
+        tcg_constant_tl(pkt->pc + pkt->encod_pkt_size_in_bytes);
+    gen_log_reg_write(HEX_REG_LR, next_PC);
+    gen_write_new_pc_pcrel(ctx, pkt, pc_off, NULL);
+}
+
+static void gen_cond_call(DisasContext *ctx, Packet *pkt,
+                          TCGv pred, bool sense, int pc_off)
+{
+    TCGv next_PC;
+    TCGv lsb = tcg_temp_local_new();
+    TCGLabel *skip = gen_new_label();
+    tcg_gen_andi_tl(lsb, pred, 1);
+    if (!sense) {
+        tcg_gen_xori_tl(lsb, lsb, 1);
+    }
+    gen_write_new_pc_pcrel(ctx, pkt, pc_off, lsb);
+    tcg_gen_brcondi_tl(TCG_COND_EQ, lsb, 0, skip);
+    tcg_temp_free(lsb);
+    next_PC =
+        tcg_constant_tl(pkt->pc + pkt->encod_pkt_size_in_bytes);
+    gen_log_reg_write(HEX_REG_LR, next_PC);
+    gen_set_label(skip);
+}
+
 static intptr_t vreg_src_off(DisasContext *ctx, int num)
 {
     intptr_t offset = offsetof(CPUHexagonState, VRegs[num]);
-- 
2.17.1