[Help-smalltalk] [PATCH] Fix JITted DeferredVariableBinding stores

[Paolo Bonzini]

This fixes both IR generation and code generation for 
DeferredVariableBinding stores.  In order to optimize the code, it is 
necessary to add an argument to BEFORE_PUSH (which stores the stack top 
on the stack).  For symmetry, I did the same for EXPORT_SP (which stores 
the stack top and additionally updates the "sp" global).

Now, only the -static issue is to be fixed before releasing rc2.

Paolo

2007-12-09  Paolo Bonzini  <address@hidden>

        * libgst/xlat.c: Fix DeferredVariableBinding stores.


--- orig/libgst/xlat.c
+++ mod/libgst/xlat.c
@@ -249,7 +249,8 @@ typedef mst_Boolean (*decode_func) (gst_
 #define TREE_BINARY_BOOL       00003   /* 2 skipped - reserved to LIT_CONST */
 #define TREE_UNARY_SPECIAL     00004
 #define TREE_UNARY_BOOL                00005
-#define TREE_DIRTY_BLOCK       00006   /* doesn't use tree->data! */
+#define TREE_STORE_LIT_VAR     00006   /* receiver in V1 */
+#define TREE_DIRTY_BLOCK       00007   /* doesn't use tree->data! */
 
 /* stack suboperations                            value of tree->data          
*/
 #define TREE_REC_VAR           00000   /* variable number */
@@ -341,6 +342,7 @@ static void gen_send (code_tree *tree);
 static void gen_binary_int (code_tree *tree);
 static void gen_pop_into_array (code_tree *tree);
 static void gen_binary_bool (code_tree *tree);
+static void gen_send_store_lit_var (code_tree *tree);
 static void gen_dirty_block (code_tree *tree);
 static void gen_unary_special (code_tree *tree);
 static void gen_unary_bool (code_tree *tree);
@@ -375,7 +377,7 @@ static void gen_invalid (code_tree *tree
 /* Function table for the code generator */
 static const emit_func emit_operation_funcs[96] = {
   gen_send, gen_binary_int, gen_invalid, gen_binary_bool,
-  gen_unary_special, gen_unary_bool, gen_dirty_block, gen_invalid,
+  gen_unary_special, gen_unary_bool, gen_send_store_lit_var, gen_dirty_block,
 
   gen_store_rec_var, gen_store_temp, gen_invalid, gen_store_lit_var,
   gen_invalid, gen_invalid, gen_store_outer, gen_pop_into_array,
@@ -1052,10 +1054,10 @@ defer_send (code_tree *tree, mst_Boolean
 /* Common pieces of code for generating stack operations */
 
 /* Save the old stack top if it was cached in V0 */
-#define BEFORE_PUSH do {                                               \
+#define BEFORE_PUSH(reg) do {                                          \
   sp_delta += sizeof (PTR);                                            \
   if (sp_delta > 0) {                                                  \
-    jit_stxi_p(sp_delta, JIT_V2, JIT_V0);                              \
+    jit_stxi_p(sp_delta, JIT_V2, (reg));                               \
   }                                                                    \
 } while(0)
 
@@ -1181,10 +1183,10 @@ defer_send (code_tree *tree, mst_Boolean
 
 /* Export V2 (the stack pointer) into the sp variable; the top of the
  * stack is assured to be in *sp, not in V0.  */
-#define EXPORT_SP do {                                                 \
+#define EXPORT_SP(reg) do {                                            \
   if (sp_delta >= 0) {                                                 \
     sp_delta += sizeof (PTR);                                          \
-    jit_stxi_p(sp_delta, JIT_V2, JIT_V0);                              \
+    jit_stxi_p(sp_delta, JIT_V2, (reg));                               \
     jit_addi_p(JIT_V2, JIT_V2, sp_delta);                              \
     jit_sti_p(&sp, JIT_V2);                                            \
     sp_delta = -sizeof (PTR);                                          \
@@ -1197,7 +1199,7 @@ defer_send (code_tree *tree, mst_Boolean
   if (sp_delta < 0) {                                                  \
     jit_ldr_p(JIT_V0, JIT_V2);                                         \
   } else {                                                             \
-    EXPORT_SP;                                                         \
+    EXPORT_SP (JIT_V0);                                                        
\
   }                                                                    \
 } while(0)
 
@@ -1413,7 +1415,7 @@ gen_send (code_tree *tree)
   if (ic->is_super)
     KEEP_V0_EXPORT_SP;
   else
-    EXPORT_SP;
+    EXPORT_SP (JIT_V0);
 
   jit_movi_ul (JIT_R0, tree->bp - bc + BYTECODE_SIZE);
   jit_ldxi_p (JIT_R1, JIT_V1, jit_field (inline_cache, cachedIP));
@@ -1807,7 +1809,7 @@ gen_binary_int (code_tree *tree)
       break;
     }
 
-  EXPORT_SP;
+  EXPORT_SP (JIT_V0);
   if (overflow)
     finish_deferred_send ();
 }
@@ -1869,12 +1871,31 @@ gen_binary_bool (code_tree *tree)
 #undef FALSE_BRANCH
 #undef FALSE_SET
 
-  EXPORT_SP;
+  EXPORT_SP (JIT_V0);
   if (deferredSend)
     finish_deferred_send ();
 }
 
 void
+gen_send_store_lit_var (code_tree *tree)
+{
+  inline_cache *ic = (inline_cache *) tree->data;
+  label *overflow;
+  int reg0, reg1;
+  OOP oop;
+  intptr_t imm;
+  jit_insn *addr;
+
+  /* tree->child = value
+     tree->child->next = var.  */
+  BEFORE_STORE;
+  emit_code_tree(tree->child->next);
+  BEFORE_PUSH (JIT_V1);
+  EXPORT_SP (JIT_V0);
+  gen_send (tree);
+}
+
+void
 gen_dirty_block (code_tree *tree)
 {
   GET_UNARY_ARG;
@@ -2117,7 +2138,7 @@ gen_store_outer (code_tree *tree)
 void
 gen_push_rec_var (code_tree *tree)
 {
-  BEFORE_PUSH;
+  BEFORE_PUSH (JIT_V0);
   CACHE_REC_VAR;
 
   jit_ldxi_p (JIT_V0, JIT_R1, REC_VAR_OFS (tree));
@@ -2127,7 +2148,7 @@ gen_push_rec_var (code_tree *tree)
 void
 gen_push_temp (code_tree *tree)
 {
-  BEFORE_PUSH;
+  BEFORE_PUSH (JIT_V0);
   CACHE_TEMP;
 
   jit_ldxi_p (JIT_V0, JIT_V1, TEMP_OFS (tree));
@@ -2137,7 +2158,7 @@ gen_push_temp (code_tree *tree)
 void
 gen_push_lit_const (code_tree *tree)
 {
-  BEFORE_PUSH;
+  BEFORE_PUSH (JIT_V0);
 
   jit_movi_p (JIT_V0, tree->data);
   self_cached = false;
@@ -2147,7 +2168,7 @@ void
 gen_push_lit_var (code_tree *tree)
 {
   char *assocOOP = ((char *) tree->data) + jit_ptr_field (OOP, object);
-  BEFORE_PUSH;
+  BEFORE_PUSH (JIT_V0);
 
   jit_ldi_p (JIT_V0, assocOOP);
   jit_ldxi_p (JIT_V0, JIT_V0, jit_ptr_field (gst_association, value));
@@ -2160,13 +2181,13 @@ gen_dup_top (code_tree *tree)
   if (sp_delta < 0)
     jit_ldr_p (JIT_V0, JIT_V2);
 
-  BEFORE_PUSH;
+  BEFORE_PUSH (JIT_V0);
 }
 
 void
 gen_push_self (code_tree *tree)
 {
-  BEFORE_PUSH;
+  BEFORE_PUSH (JIT_V0);
 
   if (!self_cached)
     jit_ldi_p (JIT_V0, &_gst_self);
@@ -2177,7 +2198,7 @@ gen_push_self (code_tree *tree)
 void
 gen_push_outer (code_tree *tree)
 {
-  BEFORE_PUSH;
+  BEFORE_PUSH (JIT_V0);
   CACHE_OUTER_CONTEXT;
 
   jit_ldxi_p (JIT_V0, JIT_V1, STACK_OFS (tree));
@@ -3388,16 +3409,16 @@ decode_bytecode (gst_uchar *bp)
                            TREE_STORE | TREE_LIT_VAR, literals[n]);
       else
        {
-         code_tree *value = pop_tree_node (NULL);
-          code_tree *var = push_tree_node_oop (IP0, NULL,
-                                              TREE_PUSH | TREE_LIT_CONST,
-                                              literals[n]);
+         code_tree *value, *var;
+          push_tree_node_oop (IP0, NULL,
+                             TREE_ALT_PUSH | TREE_LIT_CONST, literals[n]);
           inline_cache *ic =
            set_inline_cache 
(_gst_builtin_selectors[VALUE_COLON_SPECIAL].symbol,
                              1, false, TREE_SEND, 0);
 
-         var->next = value;
-         push_tree_node (IP0, var, TREE_SEND, (PTR) ic);
+         var = pop_tree_node (NULL);
+         value = pop_tree_node (var);
+         push_tree_node (IP0, value, TREE_SEND | TREE_STORE_LIT_VAR, (PTR) ic);
        }
     }