commit ae36a246ed1a0e96c6c4f478f03d047dfa3a8898
author Richard Henderson <richard.henderson@linaro.org> Tue Nov 27 13:45:08 2018 -0800
committer Richard Henderson <richard.henderson@linaro.org> Wed Dec 26 06:58:20 2018 +1100
tree 197234fae4be13f536bff405788eb2cb5210963a
parent f65a061c39cc4f9d088201031050e42eb23d5b2a

tcg: Add TCG_OPF_BB_EXIT

Use this to notice the opcodes that exit the TB, which implies
that local temps are really dead and need not be synced.

Previously we so marked the true end of the TB, but that was
immediately overwritten by the la_bb_end invoked by any
TCG_OPF_BB_END opcode, like exit_tb.

Reviewed-by: Emilio G. Cota <cota@braap.org>
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>

tcg/tcg-opc.h

diff --git a/tcg/tcg-opc.h b/tcg/tcg-opc.h
index e3a43aa..7a8a3ed 100644
--- a/tcg/tcg-opc.h
+++ b/tcg/tcg-opc.h
@@ -191,9 +191,10 @@
 /* QEMU specific */
 DEF(insn_start, 0, 0, TLADDR_ARGS * TARGET_INSN_START_WORDS,
     TCG_OPF_NOT_PRESENT)
-DEF(exit_tb, 0, 0, 1, TCG_OPF_BB_END)
-DEF(goto_tb, 0, 0, 1, TCG_OPF_BB_END)
-DEF(goto_ptr, 0, 1, 0, TCG_OPF_BB_END | IMPL(TCG_TARGET_HAS_goto_ptr))
+DEF(exit_tb, 0, 0, 1, TCG_OPF_BB_EXIT | TCG_OPF_BB_END)
+DEF(goto_tb, 0, 0, 1, TCG_OPF_BB_EXIT | TCG_OPF_BB_END)
+DEF(goto_ptr, 0, 1, 0,
+    TCG_OPF_BB_EXIT | TCG_OPF_BB_END | IMPL(TCG_TARGET_HAS_goto_ptr))
 
 DEF(qemu_ld_i32, 1, TLADDR_ARGS, 1,
     TCG_OPF_CALL_CLOBBER | TCG_OPF_SIDE_EFFECTS)

tcg/tcg.c

diff --git a/tcg/tcg.c b/tcg/tcg.c
index 4f0acf8..d40edb4 100644
--- a/tcg/tcg.c
+++ b/tcg/tcg.c
@@ -2424,6 +2424,7 @@
     int nb_temps = s->nb_temps;
     TCGOp *op, *op_prev;
 
+    /* ??? Should be redundant with the exit_tb that ends the TB.  */
     la_func_end(s, nb_globals, nb_temps);
 
     QTAILQ_FOREACH_REVERSE_SAFE(op, &s->ops, TCGOpHead, link, op_prev) {
@@ -2612,7 +2613,9 @@
             }
 
             /* if end of basic block, update */
-            if (def->flags & TCG_OPF_BB_END) {
+            if (def->flags & TCG_OPF_BB_EXIT) {
+                la_func_end(s, nb_globals, nb_temps);
+            } else if (def->flags & TCG_OPF_BB_END) {
                 la_bb_end(s, nb_globals, nb_temps);
             } else if (def->flags & TCG_OPF_SIDE_EFFECTS) {
                 la_global_sync(s, nb_globals);

tcg/tcg.h

diff --git a/tcg/tcg.h b/tcg/tcg.h
index 5e5cf68..3a62999 100644
--- a/tcg/tcg.h
+++ b/tcg/tcg.h
@@ -1030,20 +1030,22 @@
 
 /* Bits for TCGOpDef->flags, 8 bits available.  */
 enum {
+    /* Instruction exits the translation block.  */
+    TCG_OPF_BB_EXIT      = 0x01,
     /* Instruction defines the end of a basic block.  */
-    TCG_OPF_BB_END       = 0x01,
+    TCG_OPF_BB_END       = 0x02,
     /* Instruction clobbers call registers and potentially update globals.  */
-    TCG_OPF_CALL_CLOBBER = 0x02,
+    TCG_OPF_CALL_CLOBBER = 0x04,
     /* Instruction has side effects: it cannot be removed if its outputs
        are not used, and might trigger exceptions.  */
-    TCG_OPF_SIDE_EFFECTS = 0x04,
+    TCG_OPF_SIDE_EFFECTS = 0x08,
     /* Instruction operands are 64-bits (otherwise 32-bits).  */
-    TCG_OPF_64BIT        = 0x08,
+    TCG_OPF_64BIT        = 0x10,
     /* Instruction is optional and not implemented by the host, or insn
        is generic and should not be implemened by the host.  */
-    TCG_OPF_NOT_PRESENT  = 0x10,
+    TCG_OPF_NOT_PRESENT  = 0x20,
     /* Instruction operands are vectors.  */
-    TCG_OPF_VECTOR       = 0x20,
+    TCG_OPF_VECTOR       = 0x40,
 };
 
 typedef struct TCGOpDef {