GL_OES_shader_multisample_interpolation: Include scalar swizzles as valid for interpolateAt*.

Test/400.frag

@@ -126,7 +126,7 @@ void interp()
 
     interpolateAtSample(sampInArray, 1);        // ERROR
     interpolateAtSample(sampInArray[i], 0);
-    interpolateAtSample(s1.x, 2);               // ERROR
+    interpolateAtSample(s1.x, 2);
     interpolateAtSample(scalarIn, 1);
 
     interpolateAtOffset(sampInArray, vec2(0.2));         // ERROR

Test/440.frag

@@ -144,4 +144,5 @@ sample in vec3 sampInArray[4];
 void interp()
 {
     interpolateAtCentroid(sampInArray[2].xy);
+    interpolateAtSample(sampInArray[2].x.x, 2);
 }

Test/baseResults/440.frag.out

@@ -67,6 +67,16 @@ ERROR: node is still EOpNull!
 0:146              0 (const int)
 0:146            Constant:
 0:146              1 (const int)
+0:147      interpolateAtSample (global float)
+0:147        direct index (temp float)
+0:147          direct index (smooth sample temp 3-component vector of float)
+0:147            'sampInArray' (smooth sample in 4-element array of 3-component vector of float)
+0:147            Constant:
+0:147              2 (const int)
+0:147          Constant:
+0:147            0 (const int)
+0:147        Constant:
+0:147          2 (const int)
 0:?   Linker Objects
 0:?     'a' (layout(location=4 component=2 ) smooth in 2-component vector of float)
 0:?     'b' (layout(location=4 component=1 ) smooth in float)
@@ -125,6 +135,16 @@ ERROR: node is still EOpNull!
 0:146              0 (const int)
 0:146            Constant:
 0:146              1 (const int)
+0:147      interpolateAtSample (global float)
+0:147        direct index (temp float)
+0:147          direct index (smooth sample temp 3-component vector of float)
+0:147            'sampInArray' (smooth sample in 4-element array of 3-component vector of float)
+0:147            Constant:
+0:147              2 (const int)
+0:147          Constant:
+0:147            0 (const int)
+0:147        Constant:
+0:147          2 (const int)
 0:?   Linker Objects
 0:?     'a' (layout(location=4 component=2 ) smooth in 2-component vector of float)
 0:?     'b' (layout(location=4 component=1 ) smooth in float)

glslang/MachineIndependent/Intermediate.cpp

@@ -882,7 +882,9 @@ const TIntermTyped* TIntermediate::findLValueBase(const TIntermTyped* node, bool
         if (! swizzleOkay) {
             if (op == EOpVectorSwizzle)
                 return nullptr;
-            if ((op == EOpIndexDirect || op == EOpIndexIndirect) && binary->getLeft()->getType().isVector() && ! binary->getLeft()->getType().isArray())
+            if ((op == EOpIndexDirect || op == EOpIndexIndirect) && 
+                (binary->getLeft()->getType().isVector() || binary->getLeft()->getType().isScalar()) && 
+                ! binary->getLeft()->getType().isArray())
                 return nullptr;
         }
         node = node->getAsBinaryNode()->getLeft();