[PATCH for-7.1 v6 01/51] tcg: Fix indirect lowering vs TCG_OPF_COND_BRANCH

[Richard Henderson <richard.henderson@linaro.org>]

With TCG_OPF_COND_BRANCH, we extended the lifetimes of
globals across extended basic blocks.  This means that
the liveness computed in pass 1 does not kill globals
in the same way as normal temps.

Introduce TYPE_EBB to match this lifetime, so that we
get correct register allocation for the temps that we
introduce during the indirect lowering pass.

Fixes: b4cb76e6208 ("tcg: Do not kill globals at conditional branches")
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
---
 include/tcg/tcg.h |  2 ++
 tcg/tcg.c         | 10 ++++++++++
 2 files changed, 12 insertions(+)

diff --git a/include/tcg/tcg.h b/include/tcg/tcg.h
index 73869fd9d0..27de13fae0 100644
--- a/include/tcg/tcg.h
+++ b/include/tcg/tcg.h
@@ -433,6 +433,8 @@ typedef enum TCGTempVal {
 typedef enum TCGTempKind {
     /* Temp is dead at the end of all basic blocks. */
     TEMP_NORMAL,
+    /* Temp is live across conditional branch, but dead otherwise. */
+    TEMP_EBB,
     /* Temp is saved across basic blocks but dead at the end of TBs. */
     TEMP_LOCAL,
     /* Temp is saved across both basic blocks and translation blocks. */
diff --git a/tcg/tcg.c b/tcg/tcg.c
index 33a97eabdb..45030e88fd 100644
--- a/tcg/tcg.c
+++ b/tcg/tcg.c
@@ -1674,6 +1674,7 @@ static void tcg_reg_alloc_start(TCGContext *s)
         case TEMP_GLOBAL:
             break;
         case TEMP_NORMAL:
+        case TEMP_EBB:
             val = TEMP_VAL_DEAD;
             /* fall through */
         case TEMP_LOCAL:
@@ -1701,6 +1702,9 @@ static char *tcg_get_arg_str_ptr(TCGContext *s, char *buf, int buf_size,
     case TEMP_LOCAL:
         snprintf(buf, buf_size, "loc%d", idx - s->nb_globals);
         break;
+    case TEMP_EBB:
+        snprintf(buf, buf_size, "ebb%d", idx - s->nb_globals);
+        break;
     case TEMP_NORMAL:
         snprintf(buf, buf_size, "tmp%d", idx - s->nb_globals);
         break;
@@ -2378,6 +2382,7 @@ static void la_bb_end(TCGContext *s, int ng, int nt)
             state = TS_DEAD | TS_MEM;
             break;
         case TEMP_NORMAL:
+        case TEMP_EBB:
         case TEMP_CONST:
             state = TS_DEAD;
             break;
@@ -2427,6 +2432,7 @@ static void la_bb_sync(TCGContext *s, int ng, int nt)
         case TEMP_NORMAL:
             s->temps[i].state = TS_DEAD;
             break;
+        case TEMP_EBB:
         case TEMP_CONST:
             continue;
         default:
@@ -2797,6 +2803,7 @@ static bool liveness_pass_2(TCGContext *s)
             TCGTemp *dts = tcg_temp_alloc(s);
             dts->type = its->type;
             dts->base_type = its->base_type;
+            dts->kind = TEMP_EBB;
             its->state_ptr = dts;
         } else {
             its->state_ptr = NULL;
@@ -3107,6 +3114,7 @@ static void temp_free_or_dead(TCGContext *s, TCGTemp *ts, int free_or_dead)
         new_type = TEMP_VAL_MEM;
         break;
     case TEMP_NORMAL:
+    case TEMP_EBB:
         new_type = free_or_dead < 0 ? TEMP_VAL_MEM : TEMP_VAL_DEAD;
         break;
     case TEMP_CONST:
@@ -3353,6 +3361,7 @@ static void tcg_reg_alloc_bb_end(TCGContext *s, TCGRegSet allocated_regs)
             temp_save(s, ts, allocated_regs);
             break;
         case TEMP_NORMAL:
+        case TEMP_EBB:
             /* The liveness analysis already ensures that temps are dead.
                Keep an tcg_debug_assert for safety. */
             tcg_debug_assert(ts->val_type == TEMP_VAL_DEAD);
@@ -3390,6 +3399,7 @@ static void tcg_reg_alloc_cbranch(TCGContext *s, TCGRegSet allocated_regs)
         case TEMP_NORMAL:
             tcg_debug_assert(ts->val_type == TEMP_VAL_DEAD);
             break;
+        case TEMP_EBB:
         case TEMP_CONST:
             break;
         default:
-- 
2.25.1