Add foreach_unique iteration construct.

Idea via Ingo Wald / IVL compiler.

tests/foreach-unique-1.ispc

@@ -0,0 +1,14 @@
+
+export uniform int width() { return programCount; }
+
+export void f_f(uniform float RET[], uniform float aFOO[]) {
+    uniform int count = 0;
+    float a = aFOO[programIndex];
+    foreach_unique (ua in a)
+        ++count;
+    RET[programIndex] = count; 
+}
+
+export void result(uniform float RET[]) {
+    RET[programIndex] = programCount;
+}

tests/foreach-unique-2.ispc

@@ -0,0 +1,15 @@
+
+export uniform int width() { return programCount; }
+
+export void f_f(uniform float RET[], uniform float aFOO[]) {
+    uniform int count = 0;
+    float a = aFOO[programIndex];
+    // make sure a++ only evaluated once
+    foreach_unique (ua in a++)
+        ++count;
+    RET[programIndex] = a; 
+}
+
+export void result(uniform float RET[]) {
+    RET[programIndex] = programIndex + 2;
+}

tests/foreach-unique-3.ispc

@@ -0,0 +1,15 @@
+
+export uniform int width() { return programCount; }
+
+export void f_f(uniform float RET[], uniform float aFOO[]) {
+    uniform int count = 0;
+    float a = aFOO[programIndex];
+    uniform float sum = 0;
+    foreach_unique (ua in a)
+        sum += ua;
+    RET[programIndex] = sum; 
+}
+
+export void result(uniform float RET[]) {
+    RET[programIndex] = reduce_add(programIndex+1);
+}

tests/foreach-unique-4.ispc

@@ -0,0 +1,14 @@
+
+export uniform int width() { return programCount; }
+
+export void f_f(uniform float RET[], uniform float aFOO[]) {
+    uniform int count = 0;
+    int a = aFOO[programIndex];
+    foreach_unique (ua in a & 1)
+        ++count;
+    RET[programIndex] = count; 
+}
+
+export void result(uniform float RET[]) {
+    RET[programIndex] = 2;
+}

tests/foreach-unique-5.ispc

@@ -0,0 +1,15 @@
+
+export uniform int width() { return programCount; }
+
+export void f_f(uniform float RET[], uniform float aFOO[]) {
+    uniform int count = 0;
+    int a = aFOO[programIndex];
+    if (a & 1)
+        foreach_unique (ua in a & 1)
+            ++count;
+    RET[programIndex] = count; 
+}
+
+export void result(uniform float RET[]) {
+    RET[programIndex] = 1;
+}

tests/foreach-unique-6.ispc

@@ -0,0 +1,16 @@
+
+export uniform int width() { return programCount; }
+
+export void f_f(uniform float RET[], uniform float aFOO[]) {
+    uniform int count = 0;
+    float * ptr = &aFOO[programIndex];
+
+    foreach_unique (p in ptr)
+        ++count;
+
+    RET[programIndex] = count; 
+}
+
+export void result(uniform float RET[]) {
+    RET[programIndex] = programCount;
+}

tests/foreach-unique-7.ispc

@@ -0,0 +1,13 @@
+
+export uniform int width() { return programCount; }
+
+export void f_f(uniform float RET[], uniform float aFOO[]) {
+    RET[programIndex] = aFOO[programIndex]; 
+
+    foreach_unique (p in programIndex & 1)
+        RET[programIndex] = p;
+}
+
+export void result(uniform float RET[]) {
+    RET[programIndex] = programIndex & 1;
+}