tcg: Put opcodes in a linked list

The previous setup required ops and args to be completely sequential,
and was error prone when it came to both iteration and optimization.

Reviewed-by: Bastian Koppelmann <kbastian@mail.uni-paderborn.de>
Signed-off-by: Richard Henderson <rth@twiddle.net>

1 files changed, 41 insertions, 17 deletions

diff --git a/tcg/tcg.h b/tcg/tcg.h
index 95f1aad7dc..596e30a4b6 100644
--- a/tcg/tcg.h
+++ b/tcg/tcg.h
@@ -448,10 +448,28 @@ typedef struct TCGTempSet {
     unsigned long l[BITS_TO_LONGS(TCG_MAX_TEMPS)];
 } TCGTempSet;
 
+typedef struct TCGOp {
+    TCGOpcode opc   : 8;
+
+    /* The number of out and in parameter for a call.  */
+    unsigned callo  : 2;
+    unsigned calli  : 6;
+
+    /* Index of the arguments for this op, or -1 for zero-operand ops.  */
+    signed args     : 16;
+
+    /* Index of the prex/next op, or -1 for the end of the list.  */
+    signed prev     : 16;
+    signed next     : 16;
+} TCGOp;
+
+QEMU_BUILD_BUG_ON(NB_OPS > 0xff);
+QEMU_BUILD_BUG_ON(OPC_BUF_SIZE >= 0x7fff);
+QEMU_BUILD_BUG_ON(OPPARAM_BUF_SIZE >= 0x7fff);
+
 struct TCGContext {
     uint8_t *pool_cur, *pool_end;
     TCGPool *pool_first, *pool_current, *pool_first_large;
-    TCGLabel *labels;
     int nb_labels;
     int nb_globals;
     int nb_temps;
@@ -469,9 +487,6 @@ struct TCGContext {
                                corresponding output argument needs to be
                                sync to memory. */
     
-    /* tells in which temporary a given register is. It does not take
-       into account fixed registers */
-    int reg_to_temp[TCG_TARGET_NB_REGS];
     TCGRegSet reserved_regs;
     intptr_t current_frame_offset;
     intptr_t frame_start;
@@ -479,8 +494,6 @@ struct TCGContext {
     int frame_reg;
 
     tcg_insn_unit *code_ptr;
-    TCGTemp temps[TCG_MAX_TEMPS]; /* globals first, temps after */
-    TCGTempSet free_temps[TCG_TYPE_COUNT * 2];
 
     GHashTable *helpers;
 
@@ -508,14 +521,10 @@ struct TCGContext {
     int goto_tb_issue_mask;
 #endif
 
-    uint16_t gen_opc_buf[OPC_BUF_SIZE];
-    TCGArg gen_opparam_buf[OPPARAM_BUF_SIZE];
-
-    uint16_t *gen_opc_ptr;
-    TCGArg *gen_opparam_ptr;
-    target_ulong gen_opc_pc[OPC_BUF_SIZE];
-    uint16_t gen_opc_icount[OPC_BUF_SIZE];
-    uint8_t gen_opc_instr_start[OPC_BUF_SIZE];
+    int gen_first_op_idx;
+    int gen_last_op_idx;
+    int gen_next_op_idx;
+    int gen_next_parm_idx;
 
     /* Code generation.  Note that we specifically do not use tcg_insn_unit
        here, because there's too much arithmetic throughout that relies
@@ -533,6 +542,22 @@ struct TCGContext {
 
     /* The TCGBackendData structure is private to tcg-target.c.  */
     struct TCGBackendData *be;
+
+    TCGTempSet free_temps[TCG_TYPE_COUNT * 2];
+    TCGTemp temps[TCG_MAX_TEMPS]; /* globals first, temps after */
+
+    /* tells in which temporary a given register is. It does not take
+       into account fixed registers */
+    int reg_to_temp[TCG_TARGET_NB_REGS];
+
+    TCGOp gen_op_buf[OPC_BUF_SIZE];
+    TCGArg gen_opparam_buf[OPPARAM_BUF_SIZE];
+
+    target_ulong gen_opc_pc[OPC_BUF_SIZE];
+    uint16_t gen_opc_icount[OPC_BUF_SIZE];
+    uint8_t gen_opc_instr_start[OPC_BUF_SIZE];
+
+    TCGLabel labels[TCG_MAX_LABELS];
 };
 
 extern TCGContext tcg_ctx;
@@ -540,7 +565,7 @@ extern TCGContext tcg_ctx;
 /* The number of opcodes emitted so far.  */
 static inline int tcg_op_buf_count(void)
 {
-    return tcg_ctx.gen_opc_ptr - tcg_ctx.gen_opc_buf;
+    return tcg_ctx.gen_next_op_idx;
 }
 
 /* Test for whether to terminate the TB for using too many opcodes.  */
@@ -718,8 +743,7 @@ void tcg_add_target_add_op_defs(const TCGTargetOpDef *tdefs);
 void tcg_gen_callN(TCGContext *s, void *func,
                    TCGArg ret, int nargs, TCGArg *args);
 
-TCGArg *tcg_optimize(TCGContext *s, uint16_t *tcg_opc_ptr, TCGArg *args,
-                     TCGOpDef *tcg_op_def);
+void tcg_optimize(TCGContext *s);
 
 /* only used for debugging purposes */
 void tcg_dump_ops(TCGContext *s);