[mlir][spirv] Enable validation of selection and phi tests

Some of the test cases are failing as they introduced unstructured
control flow. It would be good to catch this in MLIR, but I am
not sure it is currently feasible. We could enforce the conditional
branch to always be in `spirv.mlir.selection` however from my
perspective it will break our downstream project as we rely on
unstructured control flow, i.e., the control flow graph is structured
but we do not use `spirv.mlir.selection` and `spirv.mlir.loop` as
they do not currently support early exists. It seems that the support
for early exists is slowly coming into MLIR so we probably can revise
what is being enforced regarding control flow ops in the future.

Author: IgWod-IMG

mlir/test/Target/SPIRV/phi.mlir

@@ -1,5 +1,10 @@
 // RUN: mlir-translate -no-implicit-module -split-input-file -test-spirv-roundtrip %s | FileCheck %s
 
+// RUN: %if spirv-tools %{ rm -rf %t %}
+// RUN: %if spirv-tools %{ mkdir %t %}
+// RUN: %if spirv-tools %{ mlir-translate --no-implicit-module --serialize-spirv --split-input-file --spirv-save-validation-files-with-prefix=%t/module %s %}
+// RUN: %if spirv-tools %{ spirv-val %t %}
+
 // Test branch with one block argument
 
 spirv.module Logical GLSL450 requires #spirv.vce<v1.0, [Shader], []> {
@@ -295,15 +300,26 @@ spirv.module Logical GLSL450 requires #spirv.vce<v1.0, [Shader], []> {
     %true = spirv.Constant true
     %zero = spirv.Constant 0 : i32
     %one = spirv.Constant 1 : i32
+    spirv.mlir.selection {
 // CHECK:   spirv.BranchConditional %{{.*}}, ^[[true1:.*]](%{{.*}}, %{{.*}} : i32, i32), ^[[false1:.*]]
-    spirv.BranchConditional %true, ^true1(%zero, %zero: i32, i32), ^false1
+      spirv.BranchConditional %true, ^true1(%zero, %zero: i32, i32), ^false1
 // CHECK: [[true1]](%{{.*}}: i32, %{{.*}}: i32)
-  ^true1(%arg0: i32, %arg1: i32):
-    spirv.Return
+    ^true1(%arg0: i32, %arg1: i32):
+      spirv.Return
 // CHECK: [[false1]]:
-  ^false1:
+    ^false1:
+      spirv.Return
+    ^merge:
+      spirv.mlir.merge
+    }
+
+    spirv.Return
+  }
+
+  spirv.func @main() -> () "None" {
     spirv.Return
   }
+  spirv.EntryPoint "GLCompute" @main
 }
 
 // -----
@@ -314,15 +330,26 @@ spirv.module Logical GLSL450 requires #spirv.vce<v1.0, [Shader], []> {
     %true = spirv.Constant true
     %zero = spirv.Constant 0 : i32
     %one = spirv.Constant 1 : i32
+    spirv.mlir.selection {
 // CHECK:   spirv.BranchConditional %{{.*}}, ^[[true1:.*]], ^[[false1:.*]](%{{.*}}, %{{.*}} : i32, i32)
-    spirv.BranchConditional %true, ^true1, ^false1(%zero, %zero: i32, i32)
+      spirv.BranchConditional %true, ^true1, ^false1(%zero, %zero: i32, i32)
 // CHECK: [[true1]]:
-  ^true1:
-    spirv.Return
+    ^true1:
+      spirv.Return
 // CHECK: [[false1]](%{{.*}}: i32, %{{.*}}: i32):
-  ^false1(%arg0: i32, %arg1: i32):
+    ^false1(%arg0: i32, %arg1: i32):
+      spirv.Return
+    ^merge:
+      spirv.mlir.merge
+    }
+
+    spirv.Return
+  }
+
+  spirv.func @main() -> () "None" {
     spirv.Return
   }
+  spirv.EntryPoint "GLCompute" @main
 }
 
 // -----
@@ -333,13 +360,24 @@ spirv.module Logical GLSL450 requires #spirv.vce<v1.0, [Shader], []> {
     %true = spirv.Constant true
     %zero = spirv.Constant 0 : i32
     %one = spirv.Constant 1 : i32
+    spirv.mlir.selection {
 // CHECK:   spirv.BranchConditional %{{.*}}, ^[[true1:.*]](%{{.*}} : i32), ^[[false1:.*]](%{{.*}}, %{{.*}} : i32, i32)
-    spirv.BranchConditional %true, ^true1(%one: i32), ^false1(%zero, %zero: i32, i32)
+      spirv.BranchConditional %true, ^true1(%one: i32), ^false1(%zero, %zero: i32, i32)
 // CHECK: [[true1]](%{{.*}}: i32):
-  ^true1(%arg0: i32):
-    spirv.Return
+    ^true1(%arg0: i32):
+      spirv.Return
 // CHECK: [[false1]](%{{.*}}: i32, %{{.*}}: i32):
-  ^false1(%arg1: i32, %arg2: i32):
+    ^false1(%arg1: i32, %arg2: i32):
+      spirv.Return
+    ^merge:
+      spirv.mlir.merge
+    }
+
     spirv.Return
   }
+
+  spirv.func @main() -> () "None" {
+    spirv.Return
+  }
+  spirv.EntryPoint "GLCompute" @main
 }

mlir/test/Target/SPIRV/selection.mlir

@@ -1,5 +1,10 @@
 // RUN: mlir-translate -no-implicit-module -test-spirv-roundtrip -split-input-file %s | FileCheck %s
 
+// RUN: %if spirv-tools %{ rm -rf %t %}
+// RUN: %if spirv-tools %{ mkdir %t %}
+// RUN: %if spirv-tools %{ mlir-translate --no-implicit-module --serialize-spirv --split-input-file --spirv-save-validation-files-with-prefix=%t/module %s %}
+// RUN: %if spirv-tools %{ spirv-val %t %}
+
 // Selection with both then and else branches
 
 spirv.module Logical GLSL450 requires #spirv.vce<v1.0, [Shader], []> {
@@ -136,19 +141,31 @@ spirv.module Logical GLSL450 requires #spirv.vce<v1.0, [Shader], []> {
 
 // CHECK-NEXT:    spirv.Load "Function" %[[VAR]]
     %cond = spirv.Load "Function" %var : i1
+    spirv.mlir.selection {
 //      CHECK:    spirv.BranchConditional %1, ^[[THEN1:.+]](%{{.+}} : i32), ^[[ELSE1:.+]](%{{.+}}, %{{.+}} : i32, i32)
-    spirv.BranchConditional %cond, ^then1(%one: i32), ^else1(%zero, %zero: i32, i32)
+      spirv.BranchConditional %cond, ^then1(%one: i32), ^else1(%zero, %zero: i32, i32)
 
 // CHECK-NEXT:  ^[[THEN1]](%{{.+}}: i32):
 // CHECK-NEXT:    spirv.Return
-  ^then1(%arg0: i32):
-    spirv.Return
+    ^then1(%arg0: i32):
+      spirv.Return
 
 // CHECK-NEXT:  ^[[ELSE1]](%{{.+}}: i32, %{{.+}}: i32):
 // CHECK-NEXT:    spirv.Return
-  ^else1(%arg1: i32, %arg2: i32):
+    ^else1(%arg1: i32, %arg2: i32):
+      spirv.Return
+    ^merge:
+      spirv.mlir.merge
+    }
+
     spirv.Return
   }
+
+  spirv.func @main() -> () "None" {
+    spirv.Return
+  }
+  spirv.EntryPoint "GLCompute" @main
+  spirv.ExecutionMode @main "LocalSize", 1, 1, 1
 }
 
 // -----