Split const-exprs.rs test into separate functions.

Also, just use a single out variable for each type. rather than
introducing a new output variable for every test we add.

tests/in/const-exprs.wgsl

@@ -1,14 +1,28 @@
 @group(0) @binding(0) var<storage, read_write> out: vec4<i32>;
 @group(0) @binding(1) var<storage, read_write> out2: i32;
-@group(0) @binding(2) var<storage, read_write> out3: i32;
 
 @compute @workgroup_size(1)
 fn main() {
+   swizzle_of_compose();
+   index_of_compose();
+   compose_three_deep();
+}
+
+// Swizzle the value of nested Compose expressions.
+fn swizzle_of_compose() {
    let a = vec2(1, 2);
    let b = vec2(3, 4);
-   out = vec4(a, b).wzyx;
-
-   out2 = vec4(a, b)[1];
-
-   out3 = vec4(vec3(vec2(6, 7), 8), 9)[0];
+   out = vec4(a, b).wzyx; // should assign vec4(4, 3, 2, 1);
+}
+
+// Index the value of nested Compose expressions.
+fn index_of_compose() {
+   let a = vec2(1, 2);
+   let b = vec2(3, 4);
+   out2 += vec4(a, b)[1]; // should assign 2
+}
+
+// Index the value of Compose expressions nested three deep
+fn compose_three_deep() {
+   out2 += vec4(vec3(vec2(6, 7), 8), 9)[0]; // should assign 6
 }

tests/out/glsl/const-exprs.main.Compute.glsl

@@ -9,15 +9,32 @@ layout(std430) buffer type_block_0Compute { ivec4 _group_0_binding_0_cs; };
 
 layout(std430) buffer type_1_block_1Compute { int _group_0_binding_1_cs; };
 
-layout(std430) buffer type_1_block_2Compute { int _group_0_binding_2_cs; };
 
-
-void main() {
+void swizzle_of_compose() {
     ivec2 a = ivec2(1, 2);
     ivec2 b = ivec2(3, 4);
     _group_0_binding_0_cs = ivec4(4, 3, 2, 1);
-    _group_0_binding_1_cs = 2;
-    _group_0_binding_2_cs = 6;
+    return;
+}
+
+void index_of_compose() {
+    ivec2 a_1 = ivec2(1, 2);
+    ivec2 b_1 = ivec2(3, 4);
+    int _e7 = _group_0_binding_1_cs;
+    _group_0_binding_1_cs = (_e7 + 2);
+    return;
+}
+
+void compose_three_deep() {
+    int _e2 = _group_0_binding_1_cs;
+    _group_0_binding_1_cs = (_e2 + 6);
+    return;
+}
+
+void main() {
+    swizzle_of_compose();
+    index_of_compose();
+    compose_three_deep();
     return;
 }
 

tests/out/hlsl/const-exprs.hlsl

@@ -1,14 +1,35 @@
 RWByteAddressBuffer out_ : register(u0);
 RWByteAddressBuffer out2_ : register(u1);
-RWByteAddressBuffer out3_ : register(u2);
 
-[numthreads(1, 1, 1)]
-void main()
+void swizzle_of_compose()
 {
     int2 a = int2(1, 2);
     int2 b = int2(3, 4);
     out_.Store4(0, asuint(int4(4, 3, 2, 1)));
-    out2_.Store(0, asuint(2));
-    out3_.Store(0, asuint(6));
+    return;
+}
+
+void index_of_compose()
+{
+    int2 a_1 = int2(1, 2);
+    int2 b_1 = int2(3, 4);
+    int _expr7 = asint(out2_.Load(0));
+    out2_.Store(0, asuint((_expr7 + 2)));
+    return;
+}
+
+void compose_three_deep()
+{
+    int _expr2 = asint(out2_.Load(0));
+    out2_.Store(0, asuint((_expr2 + 6)));
+    return;
+}
+
+[numthreads(1, 1, 1)]
+void main()
+{
+    swizzle_of_compose();
+    index_of_compose();
+    compose_three_deep();
     return;
 }

tests/out/msl/const-exprs.msl

@@ -5,15 +5,39 @@
 using metal::uint;
 
 
-kernel void main_(
-  device metal::int4& out [[user(fake0)]]
-, device int& out2_ [[user(fake0)]]
-, device int& out3_ [[user(fake0)]]
+void swizzle_of_compose(
+    device metal::int4& out
 ) {
     metal::int2 a = metal::int2(1, 2);
     metal::int2 b = metal::int2(3, 4);
     out = metal::int4(4, 3, 2, 1);
-    out2_ = 2;
-    out3_ = 6;
+    return;
+}
+
+void index_of_compose(
+    device int& out2_
+) {
+    metal::int2 a_1 = metal::int2(1, 2);
+    metal::int2 b_1 = metal::int2(3, 4);
+    int _e7 = out2_;
+    out2_ = _e7 + 2;
+    return;
+}
+
+void compose_three_deep(
+    device int& out2_
+) {
+    int _e2 = out2_;
+    out2_ = _e2 + 6;
+    return;
+}
+
+kernel void main_(
+  device metal::int4& out [[user(fake0)]]
+, device int& out2_ [[user(fake0)]]
+) {
+    swizzle_of_compose(out);
+    index_of_compose(out2_);
+    compose_three_deep(out2_);
     return;
 }

tests/out/spv/const-exprs.spvasm

@@ -1,13 +1,13 @@
 ; SPIR-V
 ; Version: 1.1
 ; Generator: rspirv
-; Bound: 34
+; Bound: 49
 OpCapability Shader
 OpExtension "SPV_KHR_storage_buffer_storage_class"
 %1 = OpExtInstImport "GLSL.std.450"
 OpMemoryModel Logical GLSL450
-OpEntryPoint GLCompute %16 "main"
-OpExecutionMode %16 LocalSize 1 1 1
+OpEntryPoint GLCompute %42 "main"
+OpExecutionMode %42 LocalSize 1 1 1
 OpDecorate %6 DescriptorSet 0
 OpDecorate %6 Binding 0
 OpDecorate %7 Block
@@ -16,10 +16,6 @@ OpDecorate %9 DescriptorSet 0
 OpDecorate %9 Binding 1
 OpDecorate %10 Block
 OpMemberDecorate %10 0 Offset 0
-OpDecorate %12 DescriptorSet 0
-OpDecorate %12 Binding 2
-OpDecorate %13 Block
-OpMemberDecorate %13 0 Offset 0
 %2 = OpTypeVoid
 %4 = OpTypeInt 32 1
 %3 = OpTypeVector %4 4
@@ -30,31 +26,55 @@ OpMemberDecorate %13 0 Offset 0
 %10 = OpTypeStruct %4
 %11 = OpTypePointer StorageBuffer %10
 %9 = OpVariable  %11  StorageBuffer
-%13 = OpTypeStruct %4
-%14 = OpTypePointer StorageBuffer %13
-%12 = OpVariable  %14  StorageBuffer
-%17 = OpTypeFunction %2
-%18 = OpTypePointer StorageBuffer %3
-%20 = OpTypeInt 32 0
-%19 = OpConstant  %20  0
-%22 = OpTypePointer StorageBuffer %4
-%25 = OpConstant  %4  1
-%26 = OpConstant  %4  2
-%27 = OpConstantComposite  %5  %25 %26
-%28 = OpConstant  %4  3
-%29 = OpConstant  %4  4
-%30 = OpConstantComposite  %5  %28 %29
-%31 = OpConstantComposite  %3  %29 %28 %26 %25
-%32 = OpConstant  %4  6
-%16 = OpFunction  %2  None %17
-%15 = OpLabel
-%21 = OpAccessChain  %18  %6 %19
-%23 = OpAccessChain  %22  %9 %19
-%24 = OpAccessChain  %22  %12 %19
-OpBranch %33
-%33 = OpLabel
-OpStore %21 %31
-OpStore %23 %26
-OpStore %24 %32
+%14 = OpTypeFunction %2
+%15 = OpTypePointer StorageBuffer %3
+%17 = OpTypeInt 32 0
+%16 = OpConstant  %17  0
+%19 = OpConstant  %4  1
+%20 = OpConstant  %4  2
+%21 = OpConstantComposite  %5  %19 %20
+%22 = OpConstant  %4  3
+%23 = OpConstant  %4  4
+%24 = OpConstantComposite  %5  %22 %23
+%25 = OpConstantComposite  %3  %23 %22 %20 %19
+%29 = OpTypePointer StorageBuffer %4
+%37 = OpConstant  %4  6
+%13 = OpFunction  %2  None %14
+%12 = OpLabel
+%18 = OpAccessChain  %15  %6 %16
+OpBranch %26
+%26 = OpLabel
+OpStore %18 %25
+OpReturn
+OpFunctionEnd
+%28 = OpFunction  %2  None %14
+%27 = OpLabel
+%30 = OpAccessChain  %29  %9 %16
+OpBranch %31
+%31 = OpLabel
+%32 = OpLoad  %4  %30
+%33 = OpIAdd  %4  %32 %20
+OpStore %30 %33
+OpReturn
+OpFunctionEnd
+%35 = OpFunction  %2  None %14
+%34 = OpLabel
+%36 = OpAccessChain  %29  %9 %16
+OpBranch %38
+%38 = OpLabel
+%39 = OpLoad  %4  %36
+%40 = OpIAdd  %4  %39 %37
+OpStore %36 %40
+OpReturn
+OpFunctionEnd
+%42 = OpFunction  %2  None %14
+%41 = OpLabel
+%43 = OpAccessChain  %15  %6 %16
+%44 = OpAccessChain  %29  %9 %16
+OpBranch %45
+%45 = OpLabel
+%46 = OpFunctionCall  %2  %13
+%47 = OpFunctionCall  %2  %28
+%48 = OpFunctionCall  %2  %35
 OpReturn
 OpFunctionEnd

tests/out/wgsl/const-exprs.wgsl

@@ -2,15 +2,32 @@
 var<storage, read_write> out: vec4<i32>;
 @group(0) @binding(1) 
 var<storage, read_write> out2_: i32;
-@group(0) @binding(2) 
-var<storage, read_write> out3_: i32;
 
-@compute @workgroup_size(1, 1, 1) 
-fn main() {
+fn swizzle_of_compose() {
     let a = vec2<i32>(1, 2);
     let b = vec2<i32>(3, 4);
     out = vec4<i32>(4, 3, 2, 1);
-    out2_ = 2;
-    out3_ = 6;
+    return;
+}
+
+fn index_of_compose() {
+    let a_1 = vec2<i32>(1, 2);
+    let b_1 = vec2<i32>(3, 4);
+    let _e7 = out2_;
+    out2_ = (_e7 + 2);
+    return;
+}
+
+fn compose_three_deep() {
+    let _e2 = out2_;
+    out2_ = (_e2 + 6);
+    return;
+}
+
+@compute @workgroup_size(1, 1, 1) 
+fn main() {
+    swizzle_of_compose();
+    index_of_compose();
+    compose_three_deep();
     return;
 }