tcg: Compress liveness data to 16 bits
This reduces both memory usage and per-insn cacheline usage
during code generation.
Reviewed-by: Aurelien Jarno <aurelien@aurel32.net>
Signed-off-by: Richard Henderson <rth@twiddle.net>
diff --git a/tcg/tcg.h b/tcg/tcg.h
index 6046dcd..7c0a138 100644
--- a/tcg/tcg.h
+++ b/tcg/tcg.h
@@ -575,6 +575,14 @@
unsigned long l[BITS_TO_LONGS(TCG_MAX_TEMPS)];
} TCGTempSet;
+/* While we limit helpers to 6 arguments, for 32-bit hosts, with padding,
+ this imples a max of 6*2 (64-bit in) + 2 (64-bit out) = 14 operands.
+ There are never more than 2 outputs, which means that we can store all
+ dead + sync data within 16 bits. */
+#define DEAD_ARG 4
+#define SYNC_ARG 1
+typedef uint16_t TCGLifeData;
+
typedef struct TCGOp {
TCGOpcode opc : 8;
@@ -608,12 +616,8 @@
uintptr_t *tb_jmp_target_addr; /* tb->jmp_target_addr if !USE_DIRECT_JUMP */
/* liveness analysis */
- uint16_t *op_dead_args; /* for each operation, each bit tells if the
- corresponding argument is dead */
- uint8_t *op_sync_args; /* for each operation, each bit tells if the
- corresponding output argument needs to be
- sync to memory. */
-
+ TCGLifeData *op_arg_life;
+
TCGRegSet reserved_regs;
intptr_t current_frame_offset;
intptr_t frame_start;
