spirv-reader: switch to HLSL-style pipeline IO

- When storing to sample_mask output, write to the 0th element
- Only make a return struct if it has members
- Adjust type signedness coercion when loading special builtins.
- Adapt tests

- Update expectations for end-to-end tests

- Handle sample_mask with stride
  Input variables normally don't have layout. But they can have it
  up through SPIR-V 1.4.
  Handle this case in the SPIR-V reader, by seeing through the
  intermediate alias type created for the strided array type.

Bug: tint:508
Change-Id: I0f19dc1305d3f250dbbc0698a602288c34245274
Reviewed-on: https://dawn-review.googlesource.com/c/tint/+/54743
Auto-Submit: David Neto <dneto@google.com>
Commit-Queue: Ben Clayton <bclayton@google.com>
Reviewed-by: James Price <jrprice@google.com>
Reviewed-by: Ben Clayton <bclayton@google.com>
Kokoro: Kokoro <noreply+kokoro@google.com>

test/ptr_ref/access/matrix.spvasm.expected.hlsl

@@ -1,7 +1,12 @@
-[numthreads(1, 1, 1)]
-void main() {
+void main_1() {
   float3x3 m = float3x3(float3(0.0f, 0.0f, 0.0f), float3(0.0f, 0.0f, 0.0f), float3(0.0f, 0.0f, 0.0f));
   m = float3x3(float3(1.0f, 2.0f, 3.0f), float3(4.0f, 5.0f, 6.0f), float3(7.0f, 8.0f, 9.0f));
   m[1] = float3(5.0f, 5.0f, 5.0f);
   return;
 }
+
+[numthreads(1, 1, 1)]
+void main() {
+  main_1();
+  return;
+}

test/ptr_ref/access/matrix.spvasm.expected.msl

@@ -1,10 +1,15 @@
 #include <metal_stdlib>
 
 using namespace metal;
-kernel void tint_symbol() {
+void main_1() {
   float3x3 m = float3x3(float3(0.0f, 0.0f, 0.0f), float3(0.0f, 0.0f, 0.0f), float3(0.0f, 0.0f, 0.0f));
   m = float3x3(float3(1.0f, 2.0f, 3.0f), float3(4.0f, 5.0f, 6.0f), float3(7.0f, 8.0f, 9.0f));
   m[1] = float3(5.0f, 5.0f, 5.0f);
   return;
 }
 
+kernel void tint_symbol() {
+  main_1();
+  return;
+}
+

test/ptr_ref/access/matrix.spvasm.expected.spvasm

@@ -1,14 +1,15 @@
 ; SPIR-V
 ; Version: 1.3
 ; Generator: Google Tint Compiler; 0
-; Bound: 32
+; Bound: 35
 ; Schema: 0
                OpCapability Shader
                OpMemoryModel Logical GLSL450
                OpEntryPoint GLCompute %main "main"
                OpExecutionMode %main LocalSize 1 1 1
-               OpName %main "main"
+               OpName %main_1 "main_1"
                OpName %m "m"
+               OpName %main "main"
        %void = OpTypeVoid
           %1 = OpTypeFunction %void
       %float = OpTypeFloat 32
@@ -36,7 +37,7 @@
       %int_1 = OpConstant %int 1
 %_ptr_Function_v3float = OpTypePointer Function %v3float
          %31 = OpConstantComposite %v3float %float_5 %float_5 %float_5
-       %main = OpFunction %void None %1
+     %main_1 = OpFunction %void None %1
           %4 = OpLabel
           %m = OpVariable %_ptr_Function_mat3v3float Function %13
                OpStore %m %10
@@ -45,3 +46,8 @@
                OpStore %30 %31
                OpReturn
                OpFunctionEnd
+       %main = OpFunction %void None %1
+         %33 = OpLabel
+         %34 = OpFunctionCall %void %main_1
+               OpReturn
+               OpFunctionEnd

test/ptr_ref/access/matrix.spvasm.expected.wgsl

@@ -1,7 +1,11 @@
-[[stage(compute)]]
-fn main() {
+fn main_1() {
   var m : mat3x3<f32> = mat3x3<f32>(vec3<f32>(0.0, 0.0, 0.0), vec3<f32>(0.0, 0.0, 0.0), vec3<f32>(0.0, 0.0, 0.0));
   m = mat3x3<f32>(vec3<f32>(1.0, 2.0, 3.0), vec3<f32>(4.0, 5.0, 6.0), vec3<f32>(7.0, 8.0, 9.0));
   m[1] = vec3<f32>(5.0, 5.0, 5.0);
   return;
 }
+
+[[stage(compute)]]
+fn main() {
+  main_1();
+}

test/ptr_ref/access/vector.spvasm.expected.hlsl

@@ -1,7 +1,12 @@
-[numthreads(1, 1, 1)]
-void main() {
+void main_1() {
   float3 v = float3(0.0f, 0.0f, 0.0f);
   v = float3(1.0f, 2.0f, 3.0f);
   v.y = 5.0f;
   return;
 }
+
+[numthreads(1, 1, 1)]
+void main() {
+  main_1();
+  return;
+}

test/ptr_ref/access/vector.spvasm.expected.msl

@@ -1,10 +1,15 @@
 #include <metal_stdlib>
 
 using namespace metal;
-kernel void tint_symbol() {
+void main_1() {
   float3 v = float3(0.0f, 0.0f, 0.0f);
   v = float3(1.0f, 2.0f, 3.0f);
   v.y = 5.0f;
   return;
 }
 
+kernel void tint_symbol() {
+  main_1();
+  return;
+}
+

test/ptr_ref/access/vector.spvasm.expected.spvasm

@@ -1,14 +1,15 @@
 ; SPIR-V
 ; Version: 1.3
 ; Generator: Google Tint Compiler; 0
-; Bound: 21
+; Bound: 24
 ; Schema: 0
                OpCapability Shader
                OpMemoryModel Logical GLSL450
                OpEntryPoint GLCompute %main "main"
                OpExecutionMode %main LocalSize 1 1 1
-               OpName %main "main"
+               OpName %main_1 "main_1"
                OpName %v "v"
+               OpName %main "main"
        %void = OpTypeVoid
           %1 = OpTypeFunction %void
       %float = OpTypeFloat 32
@@ -25,7 +26,7 @@
      %uint_1 = OpConstant %uint 1
 %_ptr_Function_float = OpTypePointer Function %float
     %float_5 = OpConstant %float 5
-       %main = OpFunction %void None %1
+     %main_1 = OpFunction %void None %1
           %4 = OpLabel
           %v = OpVariable %_ptr_Function_v3float Function %11
                OpStore %v %8
@@ -34,3 +35,8 @@
                OpStore %19 %float_5
                OpReturn
                OpFunctionEnd
+       %main = OpFunction %void None %1
+         %22 = OpLabel
+         %23 = OpFunctionCall %void %main_1
+               OpReturn
+               OpFunctionEnd

test/ptr_ref/access/vector.spvasm.expected.wgsl

@@ -1,7 +1,11 @@
-[[stage(compute)]]
-fn main() {
+fn main_1() {
   var v : vec3<f32> = vec3<f32>(0.0, 0.0, 0.0);
   v = vec3<f32>(1.0, 2.0, 3.0);
   v.y = 5.0;
   return;
 }
+
+[[stage(compute)]]
+fn main() {
+  main_1();
+}