Reimplement && and || to do short-circuit evaluation.

Improved shader error handling.

4 files changed, 159 insertions, 117 deletions

diff --git a/src/mesa/shader/slang/library/slang_core.gc b/src/mesa/shader/slang/library/slang_core.gc
index 407c613ab5..811568c7ba 100644
--- a/src/mesa/shader/slang/library/slang_core.gc
+++ b/src/mesa/shader/slang/library/slang_core.gc
@@ -2470,11 +2470,6 @@ bool __operator <= (const int a, const int b) {
 }
 
 
-//bool __operator ^^ (const bool a, const bool b) {
-//    return a != b;
-//}
-
-
 
 bool __logicalNot(const bool a)
 {
@@ -2483,20 +2478,6 @@ bool __logicalNot(const bool a)
    return true;
 }
 
-bool __logicalAnd(const bool a, const bool b)
-{
-   if (a)
-      return b;
-   return false;
-}
-
-bool __logicalOr(const bool a, const bool b)
-{
-   if (a)
-      return true;
-   return b;
-}
-
 bool __logicalXor(const bool a, const bool b)
 {
    // XXX   return a != b;
diff --git a/src/mesa/shader/slang/library/slang_core_gc.h b/src/mesa/shader/slang/library/slang_core_gc.h
index b1869c5d89..b34cbb89ce 100644
--- a/src/mesa/shader/slang/library/slang_core_gc.h
+++ b/src/mesa/shader/slang/library/slang_core_gc.h
@@ -805,50 +805,50 @@
 1,0,1,2,17,1,1,0,5,97,0,0,1,1,0,5,98,0,0,0,1,8,58,102,108,111,97,116,0,18,97,0,0,0,58,102,108,111,
 97,116,0,18,98,0,0,0,42,0,0,1,0,1,0,95,95,108,111,103,105,99,97,108,78,111,116,0,1,1,0,1,97,0,0,0,
 1,10,18,97,0,0,8,15,2,48,0,0,9,14,0,8,15,2,49,0,0,0,1,0,1,0,95,95,108,111,103,105,99,97,108,65,110,
-100,0,1,1,0,1,97,0,0,1,1,0,1,98,0,0,0,1,10,18,97,0,0,8,18,98,0,0,9,14,0,8,15,2,48,0,0,0,1,0,1,0,95,
-95,108,111,103,105,99,97,108,79,114,0,1,1,0,1,97,0,0,1,1,0,1,98,0,0,0,1,10,18,97,0,0,8,15,2,49,0,0,
-9,14,0,8,18,98,0,0,0,1,0,1,0,95,95,108,111,103,105,99,97,108,88,111,114,0,1,1,0,1,97,0,0,1,1,0,1,
-98,0,0,0,1,10,18,97,0,0,8,58,95,95,108,111,103,105,99,97,108,78,111,116,0,18,98,0,0,0,0,9,14,0,8,
-18,98,0,0,0,1,0,0,0,112,114,105,110,116,77,69,83,65,0,1,1,0,9,102,0,0,0,1,4,102,108,111,97,116,95,
-112,114,105,110,116,0,18,102,0,0,0,0,1,0,0,0,112,114,105,110,116,77,69,83,65,0,1,1,0,5,105,0,0,0,1,
-4,105,110,116,95,112,114,105,110,116,0,18,105,0,0,0,0,1,0,0,0,112,114,105,110,116,77,69,83,65,0,1,
-1,0,1,98,0,0,0,1,4,98,111,111,108,95,112,114,105,110,116,0,18,98,0,0,0,0,1,0,0,0,112,114,105,110,
-116,77,69,83,65,0,1,1,0,10,118,0,0,0,1,9,58,112,114,105,110,116,77,69,83,65,0,18,118,0,59,120,0,0,
-0,0,9,58,112,114,105,110,116,77,69,83,65,0,18,118,0,59,121,0,0,0,0,0,1,0,0,0,112,114,105,110,116,
-77,69,83,65,0,1,1,0,11,118,0,0,0,1,9,58,112,114,105,110,116,77,69,83,65,0,18,118,0,59,120,0,0,0,0,
-9,58,112,114,105,110,116,77,69,83,65,0,18,118,0,59,121,0,0,0,0,9,58,112,114,105,110,116,77,69,83,
-65,0,18,118,0,59,122,0,0,0,0,0,1,0,0,0,112,114,105,110,116,77,69,83,65,0,1,1,0,12,118,0,0,0,1,9,58,
-112,114,105,110,116,77,69,83,65,0,18,118,0,59,120,0,0,0,0,9,58,112,114,105,110,116,77,69,83,65,0,
-18,118,0,59,121,0,0,0,0,9,58,112,114,105,110,116,77,69,83,65,0,18,118,0,59,122,0,0,0,0,9,58,112,
-114,105,110,116,77,69,83,65,0,18,118,0,59,119,0,0,0,0,0,1,0,0,0,112,114,105,110,116,77,69,83,65,0,
-1,1,0,6,118,0,0,0,1,9,58,112,114,105,110,116,77,69,83,65,0,18,118,0,59,120,0,0,0,0,9,58,112,114,
-105,110,116,77,69,83,65,0,18,118,0,59,121,0,0,0,0,0,1,0,0,0,112,114,105,110,116,77,69,83,65,0,1,1,
-0,7,118,0,0,0,1,9,58,112,114,105,110,116,77,69,83,65,0,18,118,0,59,120,0,0,0,0,9,58,112,114,105,
-110,116,77,69,83,65,0,18,118,0,59,121,0,0,0,0,9,58,112,114,105,110,116,77,69,83,65,0,18,118,0,59,
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-9,58,112,114,105,110,116,77,69,83,65,0,18,118,0,59,120,0,0,0,0,9,58,112,114,105,110,116,77,69,83,
-65,0,18,118,0,59,121,0,0,0,0,0,1,0,0,0,112,114,105,110,116,77,69,83,65,0,1,1,0,3,118,0,0,0,1,9,58,
-112,114,105,110,116,77,69,83,65,0,18,118,0,59,120,0,0,0,0,9,58,112,114,105,110,116,77,69,83,65,0,
-18,118,0,59,121,0,0,0,0,9,58,112,114,105,110,116,77,69,83,65,0,18,118,0,59,122,0,0,0,0,0,1,0,0,0,
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+110,116,77,69,83,65,0,1,1,0,9,102,0,0,0,1,4,102,108,111,97,116,95,112,114,105,110,116,0,18,102,0,0,
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 118,0,59,120,0,0,0,0,9,58,112,114,105,110,116,77,69,83,65,0,18,118,0,59,121,0,0,0,0,9,58,112,114,
 105,110,116,77,69,83,65,0,18,118,0,59,122,0,0,0,0,9,58,112,114,105,110,116,77,69,83,65,0,18,118,0,
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-105,110,116,77,69,83,65,0,18,109,0,16,8,48,0,57,0,0,0,9,58,112,114,105,110,116,77,69,83,65,0,18,
-109,0,16,10,49,0,57,0,0,0,9,58,112,114,105,110,116,77,69,83,65,0,18,109,0,16,10,50,0,57,0,0,0,0,1,
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-110,116,77,69,83,65,0,1,1,0,18,101,0,0,0,1,4,105,110,116,95,112,114,105,110,116,0,18,101,0,0,0,0,1,
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-0,18,101,0,0,0,0,1,0,0,0,112,114,105,110,116,77,69,83,65,0,1,1,0,20,101,0,0,0,1,4,105,110,116,95,
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-1,4,105,110,116,95,112,114,105,110,116,0,18,101,0,0,0,0,0
+59,119,0,0,0,0,0,1,0,0,0,112,114,105,110,116,77,69,83,65,0,1,1,0,6,118,0,0,0,1,9,58,112,114,105,
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+116,77,69,83,65,0,18,118,0,59,120,0,0,0,0,9,58,112,114,105,110,116,77,69,83,65,0,18,118,0,59,121,0,
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+58,112,114,105,110,116,77,69,83,65,0,18,118,0,59,121,0,0,0,0,9,58,112,114,105,110,116,77,69,83,65,
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+59,120,0,0,0,0,9,58,112,114,105,110,116,77,69,83,65,0,18,118,0,59,121,0,0,0,0,9,58,112,114,105,110,
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+69,83,65,0,1,1,0,14,109,0,0,0,1,9,58,112,114,105,110,116,77,69,83,65,0,18,109,0,16,8,48,0,57,0,0,0,
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+0,18,101,0,0,0,0,1,0,0,0,112,114,105,110,116,77,69,83,65,0,1,1,0,18,101,0,0,0,1,4,105,110,116,95,
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+1,1,0,20,101,0,0,0,1,4,105,110,116,95,112,114,105,110,116,0,18,101,0,0,0,0,1,0,0,0,112,114,105,110,
+116,77,69,83,65,0,1,1,0,21,101,0,0,0,1,4,105,110,116,95,112,114,105,110,116,0,18,101,0,0,0,0,0
diff --git a/src/mesa/shader/slang/slang_codegen.c b/src/mesa/shader/slang/slang_codegen.c
index 60bf57035f..6923c00562 100644
--- a/src/mesa/shader/slang/slang_codegen.c
+++ b/src/mesa/shader/slang/slang_codegen.c
@@ -544,18 +544,11 @@ new_label(slang_atom labName)
 }
 
 static slang_ir_node *
-new_float_literal(float x, float y, float z, float w)
+new_float_literal(const float v[4])
 {
-   GLuint size;
+   const GLuint size = (v[0] == v[1] && v[0] == v[2] && v[0] == v[3]) ? 1 : 4;
    slang_ir_node *n = new_node(IR_FLOAT, NULL, NULL);
-   if (x == y && x == z && x == w)
-      size = 1;
-   else
-      size = 4;
-   n->Value[0] = x;
-   n->Value[1] = y;
-   n->Value[2] = z;
-   n->Value[3] = w;
+   COPY_4V(n->Value, v);
    /* allocate a storage object, but compute actual location (Index) later */
    n->Store = _slang_new_ir_storage(PROGRAM_CONSTANT, -1, size);
    return n;
@@ -598,10 +591,8 @@ new_var(slang_assemble_ctx *A, slang_operation *oper, slang_atom name)
 {
    slang_variable *v = _slang_locate_variable(oper->locals, name, GL_TRUE);
    slang_ir_node *n = new_node(IR_VAR, NULL, NULL);
-   if (!v) {
-      printf("VAR NOT FOUND %s\n", (char *) name);
-      assert(v);
-   }
+   if (!v)
+      return NULL;
    assert(!oper->var || oper->var == v);
    v->used = GL_TRUE;
    n->Var = v;
@@ -1626,9 +1617,12 @@ _slang_gen_select(slang_assemble_ctx *A, slang_operation *oper)
    slang_ir_node *altLab, *endLab;
    slang_ir_node *tree, *tmpDecl, *tmpVar, *cond, *cjump, *jump;
    slang_ir_node *bodx, *body, *assignx, *assigny;
-    slang_assembly_typeinfo type;
+   slang_assembly_typeinfo type;
    int size;
 
+   assert(oper->type == slang_oper_select);
+   assert(oper->num_children == 3);
+
    /* size of x or y's type */
    slang_assembly_typeinfo_construct(&type);
    _slang_typeof_operation(A, &oper->children[1], &type);
@@ -1647,10 +1641,10 @@ _slang_gen_select(slang_assemble_ctx *A, slang_operation *oper)
    cjump = new_cjump(altAtom, 0);
    tree = new_seq(tree, cjump);
 
-   /* evaluate child 2 (y) and assign to tmp */
+   /* evaluate child 1 (x) and assign to tmp */
    tmpVar = new_node(IR_VAR, NULL, NULL);
    tmpVar->Store = tmpDecl->Store;
-   body = _slang_gen_operation(A, &oper->children[2]);
+   body = _slang_gen_operation(A, &oper->children[1]);
    assigny = new_node(IR_MOVE, tmpVar, body);
    tree = new_seq(tree, assigny);
 
@@ -1662,10 +1656,10 @@ _slang_gen_select(slang_assemble_ctx *A, slang_operation *oper)
    altLab = new_label(altAtom);
    tree = new_seq(tree, altLab);
 
-   /* evaluate child 1 (x) and assign to tmp */
+   /* evaluate child 2 (y) and assign to tmp */
    tmpVar = new_node(IR_VAR, NULL, NULL);
    tmpVar->Store = tmpDecl->Store;
-   bodx = _slang_gen_operation(A, &oper->children[1]);
+   bodx = _slang_gen_operation(A, &oper->children[2]);
    assignx = new_node(IR_MOVE, tmpVar, bodx);
    tree = new_seq(tree, assignx);
 
@@ -1683,6 +1677,67 @@ _slang_gen_select(slang_assemble_ctx *A, slang_operation *oper)
 
 
 /**
+ * Generate code for &&.
+ */
+static slang_ir_node *
+_slang_gen_logical_and(slang_assemble_ctx *A, slang_operation *oper)
+{
+   /* rewrite "a && b" as  "a ? b : false" */
+   slang_operation *select;
+   slang_ir_node *n;
+
+   select = slang_operation_new(1);
+   select->type = slang_oper_select;
+   select->num_children = 3;
+   select->children = slang_operation_new(3);
+
+   slang_operation_copy(&select->children[0], &oper->children[0]);
+   slang_operation_copy(&select->children[1], &oper->children[1]);
+   select->children[2].type = slang_oper_literal_bool;
+   ASSIGN_4V(select->children[2].literal, 0, 0, 0, 0);
+
+   n = _slang_gen_select(A, select);
+
+   /* xxx wrong */
+   free(select->children);
+   free(select);
+
+   return n;
+}
+
+
+/**
+ * Generate code for ||.
+ */
+static slang_ir_node *
+_slang_gen_logical_or(slang_assemble_ctx *A, slang_operation *oper)
+{
+   /* rewrite "a || b" as  "a ? true : b" */
+   slang_operation *select;
+   slang_ir_node *n;
+
+   select = slang_operation_new(1);
+   select->type = slang_oper_select;
+   select->num_children = 3;
+   select->children = slang_operation_new(3);
+
+   slang_operation_copy(&select->children[0], &oper->children[0]);
+   select->children[1].type = slang_oper_literal_bool;
+   ASSIGN_4V(select->children[2].literal, 1, 1, 1, 1);
+   slang_operation_copy(&select->children[2], &oper->children[1]);
+
+   n = _slang_gen_select(A, select);
+
+   /* xxx wrong */
+   free(select->children);
+   free(select);
+
+   return n;
+}
+
+
+
+/**
  * Generate IR tree for a return statement.
  */
 static slang_ir_node *
@@ -1779,6 +1834,7 @@ _slang_gen_declaration(slang_assemble_ctx *A, slang_operation *oper)
    slang_ir_node *n;
    slang_ir_node *varDecl;
    slang_variable *v;
+   const char *varName = (char *) oper->a_id;
 
    assert(oper->num_children == 0 || oper->num_children == 1);
 
@@ -1792,10 +1848,10 @@ _slang_gen_declaration(slang_assemble_ctx *A, slang_operation *oper)
       slang_ir_node *var, *init, *rhs;
       assert(oper->num_children == 1);
       var = new_var(A, oper, oper->a_id);
+      if (!var) {
+         RETURN_ERROR2("Undefined variable:", varName, 0);
+      }
       /* XXX make copy of this initializer? */
-      /*
-        printf("\n*** ASSEMBLE INITIALIZER %p\n", (void*) v->initializer);
-      */
       rhs = _slang_gen_operation(A, &oper->children[0]);
       assert(rhs);
       init = new_node(IR_MOVE, var, rhs);
@@ -1805,10 +1861,10 @@ _slang_gen_declaration(slang_assemble_ctx *A, slang_operation *oper)
    else if (v->initializer) {
       slang_ir_node *var, *init, *rhs;
       var = new_var(A, oper, oper->a_id);
+      if (!var) {
+         RETURN_ERROR2("Undefined variable:", varName, 0);
+      }
       /* XXX make copy of this initializer? */
-      /*
-        printf("\n*** ASSEMBLE INITIALIZER %p\n", (void*) v->initializer);
-      */
       rhs = _slang_gen_operation(A, v->initializer);
       assert(rhs);
       init = new_node(IR_MOVE, var, rhs);
@@ -1835,9 +1891,9 @@ _slang_gen_variable(slang_assemble_ctx * A, slang_operation *oper)
     */
    slang_atom aVar = oper->var ? oper->var->a_name : oper->a_id;
    slang_ir_node *n = new_var(A, oper, aVar);
-   /*
-   assert(oper->var);
-   */
+   if (!n) {
+      RETURN_ERROR2("Undefined variable:", (char *) aVar, 0);
+   }
    return n;
 }
 
@@ -1876,18 +1932,19 @@ _slang_gen_assignment(slang_assemble_ctx * A, slang_operation *oper)
       }
       c0 = _slang_gen_operation(A, lhs);
       c1 = _slang_gen_operation(A, &oper->children[1]);
-
-      assert(c1);
-      n = new_node(IR_MOVE, c0, c1);
-      /*
-        assert(c1->Opcode != IR_SEQ);
-      */
-      if (c0->Writemask != WRITEMASK_XYZW)
-         /* XXX this is a hack! */
-         n->Writemask = c0->Writemask;
-      else
-         n->Writemask = mask;
-      return n;
+      if (c0 && c1) {
+         n = new_node(IR_MOVE, c0, c1);
+         /*assert(c1->Opcode != IR_SEQ);*/
+         if (c0->Writemask != WRITEMASK_XYZW)
+            /* XXX this is a hack! */
+            n->Writemask = c0->Writemask;
+         else
+            n->Writemask = mask;
+         return n;
+      }
+      else {
+         return NULL;
+      }
    }
 }
 
@@ -2206,25 +2263,25 @@ _slang_gen_operation(slang_assemble_ctx * A, slang_operation *oper)
 	 n = _slang_gen_function_call_name(A, "/=", oper, &oper->children[0]);
 	 return n;
       }
-   case slang_oper_logicalor:
+   case slang_oper_logicaland:
       {
 	 slang_ir_node *n;
          assert(oper->num_children == 2);
-	 n = _slang_gen_function_call_name(A, "__logicalOr", oper, NULL);
+	 n = _slang_gen_logical_and(A, oper);
 	 return n;
       }
-   case slang_oper_logicalxor:
+   case slang_oper_logicalor:
       {
 	 slang_ir_node *n;
          assert(oper->num_children == 2);
-	 n = _slang_gen_function_call_name(A, "__logicalXor", oper, NULL);
+	 n = _slang_gen_logical_or(A, oper);
 	 return n;
       }
-   case slang_oper_logicaland:
+   case slang_oper_logicalxor:
       {
 	 slang_ir_node *n;
          assert(oper->num_children == 2);
-	 n = _slang_gen_function_call_name(A, "__logicalAnd", oper, NULL);
+	 n = _slang_gen_function_call_name(A, "__logicalXor", oper, NULL);
 	 return n;
       }
    case slang_oper_not:
@@ -2239,7 +2296,7 @@ _slang_gen_operation(slang_assemble_ctx * A, slang_operation *oper)
       {
 	 slang_ir_node *n;
          assert(oper->num_children == 3);
-	 n = _slang_gen_select(A, oper );
+	 n = _slang_gen_select(A, oper);
 	 return n;
       }
 
@@ -2263,12 +2320,11 @@ _slang_gen_operation(slang_assemble_ctx * A, slang_operation *oper)
    case slang_oper_subscript:
       return _slang_gen_subscript(A, oper);
    case slang_oper_literal_float:
-      return new_float_literal(oper->literal[0], oper->literal[1],
-                               oper->literal[2], oper->literal[3]);
+      /* fall-through */
    case slang_oper_literal_int:
-      return new_float_literal(oper->literal[0], 0, 0, 0);
+      /* fall-through */
    case slang_oper_literal_bool:
-      return new_float_literal(oper->literal[0], 0, 0, 0);
+      return new_float_literal(oper->literal);
 
    case slang_oper_postincrement:   /* var++ */
       {
diff --git a/src/mesa/shader/slang/slang_emit.c b/src/mesa/shader/slang/slang_emit.c
index 9dda28d842..6c31bfc677 100644
--- a/src/mesa/shader/slang/slang_emit.c
+++ b/src/mesa/shader/slang/slang_emit.c
@@ -432,6 +432,10 @@ emit_binop(slang_var_table *vt, slang_ir_node *n, struct gl_program *prog)
 
    assert(info->InstOpcode != OPCODE_NOP);
 
+   /* XXX check if Opcode == OPCODE_ADD, then check if either child is a MUL,
+    * replace with MAD instruction.
+    */
+
    /* gen code for children */
    emit(vt, n->Children[0], prog);
    emit(vt, n->Children[1], prog);
@@ -629,7 +633,7 @@ emit_move(slang_var_table *vt, slang_ir_node *n, struct gl_program *prog)
 #endif
    {
       if (n->Children[0]->Store->Size > 4) {
-         /* move matrix/struct etc */
+         /* move matrix/struct etc (block of registers) */
          slang_ir_storage dstStore = *n->Children[0]->Store;
          slang_ir_storage srcStore = *n->Children[1]->Store;
          GLint size = srcStore.Size;
@@ -649,6 +653,7 @@ emit_move(slang_var_table *vt, slang_ir_node *n, struct gl_program *prog)
          }
       }
       else {
+         /* single register move */
          inst = new_instruction(prog, OPCODE_MOV);
          assert(n->Children[0]->Store->Index >= 0);
          assert(n->Children[0]->Store->Index < 16);
@@ -833,7 +838,7 @@ emit(slang_var_table *vt, slang_ir_node *n, struct gl_program *prog)
    case IR_FLOAT:
       /* find storage location for this float constant */
       n->Store->Index = _mesa_add_unnamed_constant(prog->Parameters, n->Value,
-                                                   n->Store->Size/*4*/,
+                                                   n->Store->Size,
                                                    &n->Store->Swizzle);
       if (n->Store->Index < 0) {
          RETURN_ERROR("Ran out of space for constants.", 0);