Factor out code generation for in-line SQL functions into a separate routine

inside of expr.c.

FossilOrigin-Name: 586a65a28fc6cac77309612abc32a2e1017c65e0387f9f438f5d8ac8406da8eb

3 files changed, 98 insertions, 47 deletions

diff --git a/src/expr.c b/src/expr.c
index e0a03d956..629768f3a 100644
--- a/src/expr.c
+++ b/src/expr.c
@@ -3573,6 +3573,69 @@ static int exprCodeVector(Parse *pParse, Expr *p, int *piFreeable){
   return iResult;
 }
 
+/*
+** Generate code to implement special SQL functions that are implemented
+** in-line rather than by using the usual callbacks.
+*/
+static int exprCodeInlineFunction(
+  Parse *pParse,        /* Parsing context */
+  ExprList *pFarg,      /* List of function arguments */
+  int iFuncId,          /* Function ID.  One of the INTFUNC_... values */
+  int target            /* Store function result in this register */
+){
+  int nFarg;
+  Vdbe *v = pParse->pVdbe;
+  assert( v!=0 );
+  assert( pFarg!=0 );
+  nFarg = pFarg->nExpr;
+  assert( nFarg>0 );  /* All in-line functions have at least one argument */
+  switch( iFuncId ){
+    case INLINEFUNC_coalesce: {
+      /* Attempt a direct implementation of the built-in COALESCE() and
+      ** IFNULL() functions.  This avoids unnecessary evaluation of
+      ** arguments past the first non-NULL argument.
+      */
+      int endCoalesce = sqlite3VdbeMakeLabel(pParse);
+      int i;
+      assert( nFarg>=2 );
+      sqlite3ExprCode(pParse, pFarg->a[0].pExpr, target);
+      for(i=1; i<nFarg; i++){
+        sqlite3VdbeAddOp2(v, OP_NotNull, target, endCoalesce);
+        VdbeCoverage(v);
+        sqlite3ExprCode(pParse, pFarg->a[i].pExpr, target);
+      }
+      sqlite3VdbeResolveLabel(v, endCoalesce);
+      break;
+    }
+
+    case INLINEFUNC_unlikely: {   
+      /* The UNLIKELY() function is a no-op.  The result is the value
+      ** of the first argument.
+      */
+      assert( nFarg>=1 );
+      target = sqlite3ExprCodeTarget(pParse, pFarg->a[0].pExpr, target);
+      break;
+    }
+
+#ifdef SQLITE_DEBUG
+    case INLINEFUNC_affinity: {
+      /* The AFFINITY() function evaluates to a string that describes
+      ** the type affinity of the argument.  This is used for testing of
+      ** the SQLite type logic.
+      */
+      const char *azAff[] = { "blob", "text", "numeric", "integer", "real" };
+      char aff;
+      assert( nFarg==1 );
+      aff = sqlite3ExprAffinity(pFarg->a[0].pExpr);
+      sqlite3VdbeLoadString(v, target, 
+              (aff<=SQLITE_AFF_NONE) ? "none" : azAff[aff-SQLITE_AFF_BLOB]);
+      break;
+    }
+#endif
+  }
+  return target;
+}
+
 
 /*
 ** Generate code into the current Vdbe to evaluate the given
@@ -3953,48 +4016,11 @@ expr_code_doover:
         sqlite3ErrorMsg(pParse, "unknown function: %s()", zId);
         break;
       }
-
-      /* Attempt a direct implementation of the built-in COALESCE() and
-      ** IFNULL() functions.  This avoids unnecessary evaluation of
-      ** arguments past the first non-NULL argument.
-      */
-      if( pDef->funcFlags & SQLITE_FUNC_COALESCE ){
-        int endCoalesce = sqlite3VdbeMakeLabel(pParse);
-        assert( nFarg>=2 );
-        sqlite3ExprCode(pParse, pFarg->a[0].pExpr, target);
-        for(i=1; i<nFarg; i++){
-          sqlite3VdbeAddOp2(v, OP_NotNull, target, endCoalesce);
-          VdbeCoverage(v);
-          sqlite3ExprCode(pParse, pFarg->a[i].pExpr, target);
-        }
-        sqlite3VdbeResolveLabel(v, endCoalesce);
-        break;
+      if( pDef->funcFlags & SQLITE_FUNC_INLINE ){
+        return exprCodeInlineFunction(pParse, pFarg,
+             SQLITE_PTR_TO_INT(pDef->pUserData), target);
       }
 
-      /* The UNLIKELY() function is a no-op.  The result is the value
-      ** of the first argument.
-      */
-      if( pDef->funcFlags & SQLITE_FUNC_UNLIKELY ){
-        assert( nFarg>=1 );
-        return sqlite3ExprCodeTarget(pParse, pFarg->a[0].pExpr, target);
-      }
-
-#ifdef SQLITE_DEBUG
-      /* The AFFINITY() function evaluates to a string that describes
-      ** the type affinity of the argument.  This is used for testing of
-      ** the SQLite type logic.
-      */
-      if( pDef->funcFlags & SQLITE_FUNC_AFFINITY ){
-        const char *azAff[] = { "blob", "text", "numeric", "integer", "real" };
-        char aff;
-        assert( nFarg==1 );
-        aff = sqlite3ExprAffinity(pFarg->a[0].pExpr);
-        sqlite3VdbeLoadString(v, target, 
-                (aff<=SQLITE_AFF_NONE) ? "none" : azAff[aff-SQLITE_AFF_BLOB]);
-        return target;
-      }
-#endif
-
       for(i=0; i<nFarg; i++){
         if( i<32 && sqlite3ExprIsConstant(pFarg->a[i].pExpr) ){
           testcase( i==31 );
diff --git a/src/func.c b/src/func.c
index d4c6936b1..31b548ff9 100644
--- a/src/func.c
+++ b/src/func.c
@@ -1921,11 +1921,11 @@ void sqlite3RegisterBuiltinFunctions(void){
     DFUNCTION(sqlite_compileoption_used,1, 0, 0, compileoptionusedFunc  ),
     DFUNCTION(sqlite_compileoption_get, 1, 0, 0, compileoptiongetFunc  ),
 #endif /* SQLITE_OMIT_COMPILEOPTION_DIAGS */
-    FUNCTION2(unlikely,          1, 0, 0, noopFunc,  SQLITE_FUNC_UNLIKELY),
-    FUNCTION2(likelihood,        2, 0, 0, noopFunc,  SQLITE_FUNC_UNLIKELY),
-    FUNCTION2(likely,            1, 0, 0, noopFunc,  SQLITE_FUNC_UNLIKELY),
+    INLINE_FUNC(unlikely,        1, INLINEFUNC_unlikely, SQLITE_FUNC_UNLIKELY),
+    INLINE_FUNC(likelihood,      2, INLINEFUNC_unlikely, SQLITE_FUNC_UNLIKELY),
+    INLINE_FUNC(likely,          1, INLINEFUNC_unlikely, SQLITE_FUNC_UNLIKELY),
 #ifdef SQLITE_DEBUG
-    FUNCTION2(affinity,          1, 0, 0, noopFunc,  SQLITE_FUNC_AFFINITY),
+    TEST_FUNC(affinity,          1, INLINEFUNC_affinity, 0),
 #endif
 #ifdef SQLITE_ENABLE_OFFSET_SQL_FUNC
     FUNCTION2(sqlite_offset,     1, 0, 0, noopFunc,  SQLITE_FUNC_OFFSET|
@@ -1959,7 +1959,7 @@ void sqlite3RegisterBuiltinFunctions(void){
     FUNCTION(upper,              1, 0, 0, upperFunc        ),
     FUNCTION(lower,              1, 0, 0, lowerFunc        ),
     FUNCTION(hex,                1, 0, 0, hexFunc          ),
-    FUNCTION2(ifnull,            2, 0, 0, noopFunc,  SQLITE_FUNC_COALESCE),
+    INLINE_FUNC(ifnull,          2, INLINEFUNC_coalesce, SQLITE_FUNC_COALESCE),
     VFUNCTION(random,            0, 0, 0, randomFunc       ),
     VFUNCTION(randomblob,        1, 0, 0, randomBlob       ),
     FUNCTION(nullif,             2, 0, 1, nullifFunc       ),
@@ -1999,7 +1999,7 @@ void sqlite3RegisterBuiltinFunctions(void){
 #endif
     FUNCTION(coalesce,           1, 0, 0, 0                ),
     FUNCTION(coalesce,           0, 0, 0, 0                ),
-    FUNCTION2(coalesce,         -1, 0, 0, noopFunc,  SQLITE_FUNC_COALESCE),
+    INLINE_FUNC(coalesce,       -1, INLINEFUNC_coalesce, SQLITE_FUNC_COALESCE),
   };
 #ifndef SQLITE_OMIT_ALTERTABLE
   sqlite3AlterFunctions();
diff --git a/src/sqliteInt.h b/src/sqliteInt.h
index 0dcb10353..d696ffd3a 100644
--- a/src/sqliteInt.h
+++ b/src/sqliteInt.h
@@ -1712,12 +1712,18 @@ struct FuncDestructor {
 #define SQLITE_FUNC_MINMAX   0x1000 /* True for min() and max() aggregates */
 #define SQLITE_FUNC_SLOCHNG  0x2000 /* "Slow Change". Value constant during a
                                     ** single query - might change over time */
-#define SQLITE_FUNC_AFFINITY 0x4000 /* Built-in affinity() function */
+#define SQLITE_FUNC_TEST     0x4000 /* Built-in testing functions */
 #define SQLITE_FUNC_OFFSET   0x8000 /* Built-in sqlite_offset() function */
 #define SQLITE_FUNC_WINDOW   0x00010000 /* Built-in window-only function */
 #define SQLITE_FUNC_INTERNAL 0x00040000 /* For use by NestedParse() only */
 #define SQLITE_FUNC_DIRECT   0x00080000 /* Not for use in TRIGGERs or VIEWs */
 #define SQLITE_FUNC_SUBTYPE  0x00100000 /* Result likely to have sub-type */
+#define SQLITE_FUNC_INLINE   0x00200000 /* Functions implemented in-line */
+
+/* Identifier numbers for each in-line function */
+#define INLINEFUNC_unlikely       0      /* unlikely(EXPR) and friends */
+#define INLINEFUNC_coalesce       1      /* coalesce(EXPR,...) */
+#define INLINEFUNC_affinity       2      /* affinity(EXPR) */
 
 /*
 ** The following three macros, FUNCTION(), LIKEFUNC() and AGGREGATE() are
@@ -1737,6 +1743,18 @@ struct FuncDestructor {
 **     Like FUNCTION except it omits the SQLITE_FUNC_CONSTANT flag and
 **     adds the SQLITE_DIRECTONLY flag.
 **
+**   INLINE_FUNC(zName, nArg, iFuncId, mFlags)
+**     zName is the name of a function that is implemented by in-line
+**     byte code rather than by the usual callbacks. The iFuncId
+**     parameter determines the function id.  The mFlags parameter is
+**     optional SQLITE_FUNC_ flags for this function.
+**
+**   TEST_FUNC(zName, nArg, iFuncId, mFlags)
+**     zName is the name of a test-only function implemented by in-line
+**     byte code rather than by the usual callbacks. The iFuncId
+**     parameter determines the function id.  The mFlags parameter is
+**     optional SQLITE_FUNC_ flags for this function.
+**
 **   DFUNCTION(zName, nArg, iArg, bNC, xFunc)
 **     Like FUNCTION except it omits the SQLITE_FUNC_CONSTANT flag and
 **     adds the SQLITE_FUNC_SLOCHNG flag.  Used for date & time functions
@@ -1779,6 +1797,13 @@ struct FuncDestructor {
 #define SFUNCTION(zName, nArg, iArg, bNC, xFunc) \
   {nArg, SQLITE_UTF8|SQLITE_DIRECTONLY, \
    SQLITE_INT_TO_PTR(iArg), 0, xFunc, 0, 0, 0, #zName, {0} }
+#define INLINE_FUNC(zName, nArg, iArg, mFlags) \
+  {nArg, SQLITE_UTF8|SQLITE_FUNC_INLINE|SQLITE_FUNC_CONSTANT|(mFlags), \
+   SQLITE_INT_TO_PTR(iArg), 0, noopFunc, 0, 0, 0, #zName, {0} }
+#define TEST_FUNC(zName, nArg, iArg, mFlags) \
+  {nArg, SQLITE_UTF8|SQLITE_FUNC_INTERNAL|SQLITE_FUNC_TEST| \
+         SQLITE_FUNC_INLINE|SQLITE_FUNC_CONSTANT|(mFlags), \
+   SQLITE_INT_TO_PTR(iArg), 0, noopFunc, 0, 0, 0, #zName, {0} }
 #define DFUNCTION(zName, nArg, iArg, bNC, xFunc) \
   {nArg, SQLITE_FUNC_SLOCHNG|SQLITE_UTF8, \
    0, 0, xFunc, 0, 0, 0, #zName, {0} }