tint: Fix DemoteToHelper for atomicCmpXchgWeak

We cannot explicitly name the result type of this builtin, so we have
to redeclare it manually.

Fixed: oss-fuzz:53347, oss-fuzz:53343
Change-Id: I23816b8b35eb20ae91472143ab30668b573d65bf
Reviewed-on: https://dawn-review.googlesource.com/c/dawn/+/110160
Commit-Queue: James Price <jrprice@google.com>
Reviewed-by: Ben Clayton <bclayton@google.com>
Kokoro: Kokoro <noreply+kokoro@google.com>
Auto-Submit: James Price <jrprice@google.com>

test/tint/statements/discard/atomic_cmpxchg.wgsl

@@ -0,0 +1,12 @@
+@group(0) @binding(0) var<storage, read_write> a : atomic<i32>;
+
+@fragment
+fn foo() -> @location(0) i32 {
+  discard;
+  var x = 0;
+  let result = atomicCompareExchangeWeak(&a, 0, 1);
+  if (result.exchanged) {
+    x = result.old_value;
+  }
+  return x;
+}

test/tint/statements/discard/atomic_cmpxchg.wgsl.expected.dxc.hlsl

@@ -0,0 +1,50 @@
+static bool tint_discarded = false;
+
+struct tint_symbol_2 {
+  int old_value;
+  bool exchanged;
+};
+
+RWByteAddressBuffer a : register(u0, space0);
+
+struct tint_symbol {
+  int value : SV_Target0;
+};
+struct atomic_compare_exchange_weak_ret_type {
+  int old_value;
+  bool exchanged;
+};
+
+atomic_compare_exchange_weak_ret_type tint_atomicCompareExchangeWeak(RWByteAddressBuffer buffer, uint offset, int compare, int value) {
+  atomic_compare_exchange_weak_ret_type result=(atomic_compare_exchange_weak_ret_type)0;
+  buffer.InterlockedCompareExchange(offset, compare, value, result.old_value);
+  result.exchanged = result.old_value == compare;
+  return result;
+}
+
+
+int foo_inner() {
+  tint_discarded = true;
+  int x = 0;
+  tint_symbol_2 tint_symbol_1 = (tint_symbol_2)0;
+  if (!(tint_discarded)) {
+    const atomic_compare_exchange_weak_ret_type tint_symbol_3 = tint_atomicCompareExchangeWeak(a, 0u, 0, 1);
+    tint_symbol_1.old_value = tint_symbol_3.old_value;
+    tint_symbol_1.exchanged = tint_symbol_3.exchanged;
+  }
+  const tint_symbol_2 result = tint_symbol_1;
+  if (result.exchanged) {
+    x = result.old_value;
+  }
+  return x;
+}
+
+tint_symbol foo() {
+  const int inner_result = foo_inner();
+  tint_symbol wrapper_result = (tint_symbol)0;
+  wrapper_result.value = inner_result;
+  if (tint_discarded) {
+    discard;
+  }
+  return wrapper_result;
+}

test/tint/statements/discard/atomic_cmpxchg.wgsl.expected.fxc.hlsl

@@ -0,0 +1,50 @@
+static bool tint_discarded = false;
+
+struct tint_symbol_2 {
+  int old_value;
+  bool exchanged;
+};
+
+RWByteAddressBuffer a : register(u0, space0);
+
+struct tint_symbol {
+  int value : SV_Target0;
+};
+struct atomic_compare_exchange_weak_ret_type {
+  int old_value;
+  bool exchanged;
+};
+
+atomic_compare_exchange_weak_ret_type tint_atomicCompareExchangeWeak(RWByteAddressBuffer buffer, uint offset, int compare, int value) {
+  atomic_compare_exchange_weak_ret_type result=(atomic_compare_exchange_weak_ret_type)0;
+  buffer.InterlockedCompareExchange(offset, compare, value, result.old_value);
+  result.exchanged = result.old_value == compare;
+  return result;
+}
+
+
+int foo_inner() {
+  tint_discarded = true;
+  int x = 0;
+  tint_symbol_2 tint_symbol_1 = (tint_symbol_2)0;
+  if (!(tint_discarded)) {
+    const atomic_compare_exchange_weak_ret_type tint_symbol_3 = tint_atomicCompareExchangeWeak(a, 0u, 0, 1);
+    tint_symbol_1.old_value = tint_symbol_3.old_value;
+    tint_symbol_1.exchanged = tint_symbol_3.exchanged;
+  }
+  const tint_symbol_2 result = tint_symbol_1;
+  if (result.exchanged) {
+    x = result.old_value;
+  }
+  return x;
+}
+
+tint_symbol foo() {
+  const int inner_result = foo_inner();
+  tint_symbol wrapper_result = (tint_symbol)0;
+  wrapper_result.value = inner_result;
+  if (tint_discarded) {
+    discard;
+  }
+  return wrapper_result;
+}

test/tint/statements/discard/atomic_cmpxchg.wgsl.expected.glsl

@@ -0,0 +1,47 @@
+#version 310 es
+precision mediump float;
+
+struct atomic_compare_exchange_resulti32 {
+  int old_value;
+  bool exchanged;
+};
+
+
+bool tint_discarded = false;
+struct tint_symbol_1 {
+  int old_value;
+  bool exchanged;
+};
+
+layout(location = 0) out int value;
+layout(binding = 0, std430) buffer a_block_ssbo {
+  int inner;
+} a;
+
+int foo() {
+  tint_discarded = true;
+  int x = 0;
+  tint_symbol_1 tint_symbol = tint_symbol_1(0, false);
+  if (!(tint_discarded)) {
+    atomic_compare_exchange_resulti32 atomic_compare_result;
+    atomic_compare_result.old_value = atomicCompSwap(a.inner, 0, 1);
+    atomic_compare_result.exchanged = atomic_compare_result.old_value == 0;
+    atomic_compare_exchange_resulti32 tint_symbol_2 = atomic_compare_result;
+    tint_symbol.old_value = tint_symbol_2.old_value;
+    tint_symbol.exchanged = tint_symbol_2.exchanged;
+  }
+  tint_symbol_1 result = tint_symbol;
+  if (result.exchanged) {
+    x = result.old_value;
+  }
+  return x;
+}
+
+void main() {
+  int inner_result = foo();
+  value = inner_result;
+  if (tint_discarded) {
+    discard;
+  }
+  return;
+}

test/tint/statements/discard/atomic_cmpxchg.wgsl.expected.msl

@@ -0,0 +1,50 @@
+#include <metal_stdlib>
+
+using namespace metal;
+
+struct atomic_compare_exchange_resulti32 {
+  int old_value;
+  bool exchanged;
+};
+atomic_compare_exchange_resulti32 atomicCompareExchangeWeak_1(device atomic_int* atomic, int compare, int value) {
+  int old_value = compare;
+  bool exchanged = atomic_compare_exchange_weak_explicit(atomic, &old_value, value, memory_order_relaxed, memory_order_relaxed);
+  return {old_value, exchanged};
+}
+
+struct tint_symbol_2 {
+  int old_value;
+  bool exchanged;
+};
+
+struct tint_symbol {
+  int value [[color(0)]];
+};
+
+int foo_inner(thread bool* const tint_symbol_4, device atomic_int* const tint_symbol_5) {
+  *(tint_symbol_4) = true;
+  int x = 0;
+  tint_symbol_2 tint_symbol_1 = {};
+  if (!(*(tint_symbol_4))) {
+    atomic_compare_exchange_resulti32 const tint_symbol_3 = atomicCompareExchangeWeak_1(tint_symbol_5, 0, 1);
+    tint_symbol_1.old_value = tint_symbol_3.old_value;
+    tint_symbol_1.exchanged = tint_symbol_3.exchanged;
+  }
+  tint_symbol_2 const result = tint_symbol_1;
+  if (result.exchanged) {
+    x = result.old_value;
+  }
+  return x;
+}
+
+fragment tint_symbol foo(device atomic_int* tint_symbol_7 [[buffer(0)]]) {
+  thread bool tint_symbol_6 = false;
+  int const inner_result = foo_inner(&(tint_symbol_6), tint_symbol_7);
+  tint_symbol wrapper_result = {};
+  wrapper_result.value = inner_result;
+  if (tint_symbol_6) {
+    discard_fragment();
+  }
+  return wrapper_result;
+}
+

test/tint/statements/discard/atomic_cmpxchg.wgsl.expected.spvasm

@@ -0,0 +1,106 @@
+; SPIR-V
+; Version: 1.3
+; Generator: Google Tint Compiler; 0
+; Bound: 56
+; Schema: 0
+               OpCapability Shader
+               OpMemoryModel Logical GLSL450
+               OpEntryPoint Fragment %foo "foo" %value
+               OpExecutionMode %foo OriginUpperLeft
+               OpName %tint_discarded "tint_discarded"
+               OpName %value "value"
+               OpName %a_block "a_block"
+               OpMemberName %a_block 0 "inner"
+               OpName %a "a"
+               OpName %foo_inner "foo_inner"
+               OpName %x "x"
+               OpName %tint_symbol_1 "tint_symbol_1"
+               OpMemberName %tint_symbol_1 0 "old_value"
+               OpMemberName %tint_symbol_1 1 "exchanged"
+               OpName %tint_symbol "tint_symbol"
+               OpName %__atomic_compare_exchange_resulti32 "__atomic_compare_exchange_resulti32"
+               OpMemberName %__atomic_compare_exchange_resulti32 0 "old_value"
+               OpMemberName %__atomic_compare_exchange_resulti32 1 "exchanged"
+               OpName %foo "foo"
+               OpDecorate %value Location 0
+               OpDecorate %a_block Block
+               OpMemberDecorate %a_block 0 Offset 0
+               OpDecorate %a DescriptorSet 0
+               OpDecorate %a Binding 0
+               OpMemberDecorate %tint_symbol_1 0 Offset 0
+               OpMemberDecorate %tint_symbol_1 1 Offset 4
+               OpMemberDecorate %__atomic_compare_exchange_resulti32 0 Offset 0
+               OpMemberDecorate %__atomic_compare_exchange_resulti32 1 Offset 4
+       %bool = OpTypeBool
+          %2 = OpConstantNull %bool
+%_ptr_Private_bool = OpTypePointer Private %bool
+%tint_discarded = OpVariable %_ptr_Private_bool Private %2
+        %int = OpTypeInt 32 1
+%_ptr_Output_int = OpTypePointer Output %int
+          %8 = OpConstantNull %int
+      %value = OpVariable %_ptr_Output_int Output %8
+    %a_block = OpTypeStruct %int
+%_ptr_StorageBuffer_a_block = OpTypePointer StorageBuffer %a_block
+          %a = OpVariable %_ptr_StorageBuffer_a_block StorageBuffer
+         %12 = OpTypeFunction %int
+       %true = OpConstantTrue %bool
+%_ptr_Function_int = OpTypePointer Function %int
+%tint_symbol_1 = OpTypeStruct %int %bool
+%_ptr_Function_tint_symbol_1 = OpTypePointer Function %tint_symbol_1
+         %21 = OpConstantNull %tint_symbol_1
+%__atomic_compare_exchange_resulti32 = OpTypeStruct %int %bool
+       %uint = OpTypeInt 32 0
+     %uint_1 = OpConstant %uint 1
+     %uint_0 = OpConstant %uint 0
+%_ptr_StorageBuffer_int = OpTypePointer StorageBuffer %int
+      %int_1 = OpConstant %int 1
+%_ptr_Function_bool = OpTypePointer Function %bool
+       %void = OpTypeVoid
+         %48 = OpTypeFunction %void
+  %foo_inner = OpFunction %int None %12
+         %14 = OpLabel
+          %x = OpVariable %_ptr_Function_int Function %8
+%tint_symbol = OpVariable %_ptr_Function_tint_symbol_1 Function %21
+               OpStore %tint_discarded %true
+               OpStore %x %8
+         %23 = OpLoad %bool %tint_discarded
+         %22 = OpLogicalNot %bool %23
+               OpSelectionMerge %24 None
+               OpBranchConditional %22 %25 %24
+         %25 = OpLabel
+         %33 = OpAccessChain %_ptr_StorageBuffer_int %a %uint_0
+         %35 = OpAtomicCompareExchange %int %33 %uint_1 %uint_0 %uint_0 %int_1 %8
+         %36 = OpIEqual %bool %35 %8
+         %26 = OpCompositeConstruct %__atomic_compare_exchange_resulti32 %35 %36
+         %37 = OpAccessChain %_ptr_Function_int %tint_symbol %uint_0
+         %38 = OpCompositeExtract %int %26 0
+               OpStore %37 %38
+         %40 = OpAccessChain %_ptr_Function_bool %tint_symbol %uint_1
+         %41 = OpCompositeExtract %bool %26 1
+               OpStore %40 %41
+               OpBranch %24
+         %24 = OpLabel
+         %42 = OpLoad %tint_symbol_1 %tint_symbol
+         %43 = OpCompositeExtract %bool %42 1
+               OpSelectionMerge %44 None
+               OpBranchConditional %43 %45 %44
+         %45 = OpLabel
+         %46 = OpCompositeExtract %int %42 0
+               OpStore %x %46
+               OpBranch %44
+         %44 = OpLabel
+         %47 = OpLoad %int %x
+               OpReturnValue %47
+               OpFunctionEnd
+        %foo = OpFunction %void None %48
+         %51 = OpLabel
+         %52 = OpFunctionCall %int %foo_inner
+               OpStore %value %52
+         %53 = OpLoad %bool %tint_discarded
+               OpSelectionMerge %54 None
+               OpBranchConditional %53 %55 %54
+         %55 = OpLabel
+               OpKill
+         %54 = OpLabel
+               OpReturn
+               OpFunctionEnd

test/tint/statements/discard/atomic_cmpxchg.wgsl.expected.wgsl

@@ -0,0 +1,12 @@
+@group(0) @binding(0) var<storage, read_write> a : atomic<i32>;
+
+@fragment
+fn foo() -> @location(0) i32 {
+  discard;
+  var x = 0;
+  let result = atomicCompareExchangeWeak(&(a), 0, 1);
+  if (result.exchanged) {
+    x = result.old_value;
+  }
+  return x;
+}