tint/test-runner: Split expectations for FXC and DXC

Change tint's `--fxc` flag to take the path of the FXC compiler DLL.
Have tint attempt to validate with both FXC and DXC if `--validate` is
passed.

Fix the 'dirsWithNoPassExpectations' logic which looks like it got
broken with the tint -> dawn merge. It also incorrectly applied
filepath.FromSlash() on windows.

Change-Id: I0f46aa5c21bc48a2abc48402c41f846aff4a8633
Reviewed-on: https://dawn-review.googlesource.com/c/dawn/+/96800
Reviewed-by: Antonio Maiorano <amaiorano@google.com>
Commit-Queue: Ben Clayton <bclayton@chromium.org>

test/tint/statements/increment/array_element.wgsl.expected.fxc.hlsl

@@ -0,0 +1,10 @@
+[numthreads(1, 1, 1)]
+void unused_entry_point() {
+  return;
+}
+
+RWByteAddressBuffer a : register(u0, space0);
+
+void main() {
+  a.Store(4u, asuint((a.Load(4u) + 1u)));
+}

test/tint/statements/increment/complex.wgsl.expected.fxc.hlsl

@@ -0,0 +1,63 @@
+[numthreads(1, 1, 1)]
+void unused_entry_point() {
+  return;
+}
+
+RWByteAddressBuffer buffer : register(u0, space0);
+static uint v = 0u;
+
+int idx1() {
+  v = (v + 1u);
+  return 1;
+}
+
+int idx2() {
+  v = (v + 1u);
+  return 2;
+}
+
+int idx3() {
+  v = (v + 1u);
+  return 3;
+}
+
+int idx4() {
+  v = (v + 1u);
+  return 4;
+}
+
+int idx5() {
+  v = (v + 1u);
+  return 0;
+}
+
+int idx6() {
+  v = (v + 1u);
+  return 2;
+}
+
+void main() {
+  const int tint_symbol_4 = idx1();
+  const int tint_symbol_5 = idx2();
+  const int tint_symbol_save = tint_symbol_4;
+  const int tint_symbol_save_1 = tint_symbol_5;
+  const int tint_symbol_1 = idx3();
+  {
+    buffer.Store((((64u * uint(tint_symbol_save)) + (16u * uint(tint_symbol_save_1))) + (4u * uint(tint_symbol_1))), asuint((asint(buffer.Load((((64u * uint(tint_symbol_save)) + (16u * uint(tint_symbol_save_1))) + (4u * uint(tint_symbol_1))))) + 1)));
+    [loop] while (true) {
+      if (!((v < 10u))) {
+        break;
+      }
+      {
+      }
+      {
+        const int tint_symbol_6 = idx4();
+        const int tint_symbol_7 = idx5();
+        const int tint_symbol_2_save = tint_symbol_6;
+        const int tint_symbol_2_save_1 = tint_symbol_7;
+        const int tint_symbol_3 = idx6();
+        buffer.Store((((64u * uint(tint_symbol_2_save)) + (16u * uint(tint_symbol_2_save_1))) + (4u * uint(tint_symbol_3))), asuint((asint(buffer.Load((((64u * uint(tint_symbol_2_save)) + (16u * uint(tint_symbol_2_save_1))) + (4u * uint(tint_symbol_3))))) + 1)));
+      }
+    }
+  }
+}

test/tint/statements/increment/for_loop_continuing.wgsl.expected.fxc.hlsl

@@ -0,0 +1,13 @@
+[numthreads(1, 1, 1)]
+void unused_entry_point() {
+  return;
+}
+
+RWByteAddressBuffer i : register(u0, space0);
+
+void main() {
+  {
+    [loop] for(; (i.Load(0u) < 10u); i.Store(0u, asuint((i.Load(0u) + 1u)))) {
+    }
+  }
+}

test/tint/statements/increment/for_loop_initializer.wgsl.expected.fxc.hlsl

@@ -0,0 +1,13 @@
+[numthreads(1, 1, 1)]
+void unused_entry_point() {
+  return;
+}
+
+RWByteAddressBuffer i : register(u0, space0);
+
+void main() {
+  {
+    [loop] for(i.Store(0u, asuint((i.Load(0u) + 1u))); (i.Load(0u) < 10u); ) {
+    }
+  }
+}

test/tint/statements/increment/function.wgsl.expected.fxc.hlsl

@@ -0,0 +1,9 @@
+[numthreads(1, 1, 1)]
+void unused_entry_point() {
+  return;
+}
+
+void main() {
+  int i = 0;
+  i = (i + 1);
+}

test/tint/statements/increment/private.wgsl.expected.fxc.hlsl

@@ -0,0 +1,10 @@
+[numthreads(1, 1, 1)]
+void unused_entry_point() {
+  return;
+}
+
+static int i = 0;
+
+void main() {
+  i = (i + 1);
+}

test/tint/statements/increment/storage.wgsl.expected.fxc.hlsl

@@ -0,0 +1,10 @@
+[numthreads(1, 1, 1)]
+void unused_entry_point() {
+  return;
+}
+
+RWByteAddressBuffer i : register(u0, space0);
+
+void main() {
+  i.Store(0u, asuint((i.Load(0u) + 1u)));
+}

test/tint/statements/increment/vector_component.wgsl.expected.fxc.hlsl

@@ -0,0 +1,12 @@
+[numthreads(1, 1, 1)]
+void unused_entry_point() {
+  return;
+}
+
+RWByteAddressBuffer a : register(u0, space0);
+
+void main() {
+  const int tint_symbol_1 = 1;
+  a.Store((4u * uint(tint_symbol_1)), asuint((a.Load((4u * uint(tint_symbol_1))) + 1u)));
+  a.Store(8u, asuint((a.Load(8u) + 1u)));
+}

test/tint/statements/increment/workgroup.wgsl.expected.fxc.hlsl

@@ -0,0 +1,10 @@
+[numthreads(1, 1, 1)]
+void unused_entry_point() {
+  return;
+}
+
+groupshared int i;
+
+void main() {
+  i = (i + 1);
+}