tint: transform::RemovePhonies: skip builtins with no side effects

This transform was attempting to remove builtins with no side
effects, such as a call with abstract int/float args, which is unhandled
by this transform. For example, this would cause the transform to ICE:

_ = clamp(1, 2, 3);

Fixes ClusterFuzz issue crbug.com/1348739.

Bug: chromium:1348739
Change-Id: Ie355eb36c6c020417c2d93f2dc434c11dbb72d1f
Reviewed-on: https://dawn-review.googlesource.com/c/dawn/+/97880
Kokoro: Kokoro <noreply+kokoro@google.com>
Commit-Queue: Antonio Maiorano <amaiorano@google.com>
Reviewed-by: Ben Clayton <bclayton@google.com>

src/tint/transform/remove_phonies.cc

@@ -97,7 +97,8 @@ void RemovePhonies::Run(CloneContext& ctx, const DataMap&, DataMap&) const {
                                 // Just skip.
                                 return ast::TraverseAction::Skip;
                             }
-                            if (call->Target()->IsAnyOf<sem::Function, sem::Builtin>()) {
+                            if (call->Target()->IsAnyOf<sem::Function, sem::Builtin>() &&
+                                call->HasSideEffects()) {
                                 side_effects.push_back(expr);
                                 return ast::TraverseAction::Skip;
                             }

src/tint/transform/remove_phonies_test.cc

@@ -65,6 +65,8 @@ fn f() {
   _ = vec2<f32>(5.0);
   _ = vec3<i32>(6, 7, 8);
   _ = mat2x2<f32>(9.0, 10.0, 11.0, 12.0);
+  _ = atan2(1.0, 2.0);
+  _ = clamp(1.0, 2.0, 3.0);
 }
 )";
 

test/tint/bug/chromium/1341475.wgsl

@@ -1,4 +1,4 @@
 @compute @workgroup_size(1)
 fn main() {
-    _ = mix(1.0, vec2(1.0).y, 1.0);
+    let a = mix(1.0, vec2(1.0).y, 1.0);
 }

test/tint/bug/chromium/1341475.wgsl.expected.dxc.hlsl

@@ -1,5 +1,5 @@
 [numthreads(1, 1, 1)]
 void main() {
-  lerp(1.0f, 1.0f, 1.0f);
+  const float a = lerp(1.0f, 1.0f, 1.0f);
   return;
 }

test/tint/bug/chromium/1341475.wgsl.expected.fxc.hlsl

@@ -1,5 +1,5 @@
 [numthreads(1, 1, 1)]
 void main() {
-  lerp(1.0f, 1.0f, 1.0f);
+  const float a = lerp(1.0f, 1.0f, 1.0f);
   return;
 }

test/tint/bug/chromium/1341475.wgsl.expected.glsl

@@ -1,7 +1,7 @@
 #version 310 es
 
 void tint_symbol() {
-  mix(1.0f, 1.0f, 1.0f);
+  float a = mix(1.0f, 1.0f, 1.0f);
 }
 
 layout(local_size_x = 1, local_size_y = 1, local_size_z = 1) in;

test/tint/bug/chromium/1341475.wgsl.expected.msl

@@ -2,7 +2,7 @@
 
 using namespace metal;
 kernel void tint_symbol() {
-  mix(1.0f, 1.0f, 1.0f);
+  float const a = mix(1.0f, 1.0f, 1.0f);
   return;
 }
 

test/tint/bug/chromium/1341475.wgsl.expected.wgsl

@@ -1,4 +1,4 @@
 @compute @workgroup_size(1)
 fn main() {
-  _ = mix(1.0, vec2(1.0).y, 1.0);
+  let a = mix(1.0, vec2(1.0).y, 1.0);
 }

test/tint/builtins/repeated_use.wgsl

@@ -2,19 +2,19 @@
 // same builtin overload results in single helper being generated.
 @compute @workgroup_size(1)
 fn main() {
-    _ = degrees(vec4<f32>());
-    _ = degrees(vec4<f32>(1.));
-    _ = degrees(vec4<f32>(1., 2., 3., 4.));
+    let a = degrees(vec4<f32>());
+    let b = degrees(vec4<f32>(1.));
+    let c = degrees(vec4<f32>(1., 2., 3., 4.));
 
-    _ = degrees(vec3<f32>());
-    _ = degrees(vec3<f32>(1.));
-    _ = degrees(vec3<f32>(1., 2., 3.));
+    let d = degrees(vec3<f32>());
+    let e = degrees(vec3<f32>(1.));
+    let f = degrees(vec3<f32>(1., 2., 3.));
 
-    _ = degrees(vec2<f32>());
-    _ = degrees(vec2<f32>(1.));
-    _ = degrees(vec2<f32>(1., 2.));
+    let g = degrees(vec2<f32>());
+    let h = degrees(vec2<f32>(1.));
+    let i = degrees(vec2<f32>(1., 2.));
 
-    _ = degrees(1.);
-    _ = degrees(2.);
-    _ = degrees(3.);
+    let j = degrees(1.);
+    let k = degrees(2.);
+    let l = degrees(3.);
 }

test/tint/builtins/repeated_use.wgsl.expected.dxc.hlsl

@@ -16,17 +16,17 @@ float tint_degrees_3(float param_0) {
 
 [numthreads(1, 1, 1)]
 void main() {
-  tint_degrees((0.0f).xxxx);
-  tint_degrees((1.0f).xxxx);
-  tint_degrees(float4(1.0f, 2.0f, 3.0f, 4.0f));
-  tint_degrees_1((0.0f).xxx);
-  tint_degrees_1((1.0f).xxx);
-  tint_degrees_1(float3(1.0f, 2.0f, 3.0f));
-  tint_degrees_2((0.0f).xx);
-  tint_degrees_2((1.0f).xx);
-  tint_degrees_2(float2(1.0f, 2.0f));
-  tint_degrees_3(1.0f);
-  tint_degrees_3(2.0f);
-  tint_degrees_3(3.0f);
+  const float4 a = tint_degrees((0.0f).xxxx);
+  const float4 b = tint_degrees((1.0f).xxxx);
+  const float4 c = tint_degrees(float4(1.0f, 2.0f, 3.0f, 4.0f));
+  const float3 d = tint_degrees_1((0.0f).xxx);
+  const float3 e = tint_degrees_1((1.0f).xxx);
+  const float3 f = tint_degrees_1(float3(1.0f, 2.0f, 3.0f));
+  const float2 g = tint_degrees_2((0.0f).xx);
+  const float2 h = tint_degrees_2((1.0f).xx);
+  const float2 i = tint_degrees_2(float2(1.0f, 2.0f));
+  const float j = tint_degrees_3(1.0f);
+  const float k = tint_degrees_3(2.0f);
+  const float l = tint_degrees_3(3.0f);
   return;
 }

test/tint/builtins/repeated_use.wgsl.expected.fxc.hlsl

@@ -16,17 +16,17 @@ float tint_degrees_3(float param_0) {
 
 [numthreads(1, 1, 1)]
 void main() {
-  tint_degrees((0.0f).xxxx);
-  tint_degrees((1.0f).xxxx);
-  tint_degrees(float4(1.0f, 2.0f, 3.0f, 4.0f));
-  tint_degrees_1((0.0f).xxx);
-  tint_degrees_1((1.0f).xxx);
-  tint_degrees_1(float3(1.0f, 2.0f, 3.0f));
-  tint_degrees_2((0.0f).xx);
-  tint_degrees_2((1.0f).xx);
-  tint_degrees_2(float2(1.0f, 2.0f));
-  tint_degrees_3(1.0f);
-  tint_degrees_3(2.0f);
-  tint_degrees_3(3.0f);
+  const float4 a = tint_degrees((0.0f).xxxx);
+  const float4 b = tint_degrees((1.0f).xxxx);
+  const float4 c = tint_degrees(float4(1.0f, 2.0f, 3.0f, 4.0f));
+  const float3 d = tint_degrees_1((0.0f).xxx);
+  const float3 e = tint_degrees_1((1.0f).xxx);
+  const float3 f = tint_degrees_1(float3(1.0f, 2.0f, 3.0f));
+  const float2 g = tint_degrees_2((0.0f).xx);
+  const float2 h = tint_degrees_2((1.0f).xx);
+  const float2 i = tint_degrees_2(float2(1.0f, 2.0f));
+  const float j = tint_degrees_3(1.0f);
+  const float k = tint_degrees_3(2.0f);
+  const float l = tint_degrees_3(3.0f);
   return;
 }

test/tint/builtins/repeated_use.wgsl.expected.glsl

@@ -18,18 +18,18 @@ float tint_degrees_3(float param_0) {
 
 
 void tint_symbol() {
-  tint_degrees(vec4(0.0f));
-  tint_degrees(vec4(1.0f));
-  tint_degrees(vec4(1.0f, 2.0f, 3.0f, 4.0f));
-  tint_degrees_1(vec3(0.0f));
-  tint_degrees_1(vec3(1.0f));
-  tint_degrees_1(vec3(1.0f, 2.0f, 3.0f));
-  tint_degrees_2(vec2(0.0f));
-  tint_degrees_2(vec2(1.0f));
-  tint_degrees_2(vec2(1.0f, 2.0f));
-  tint_degrees_3(1.0f);
-  tint_degrees_3(2.0f);
-  tint_degrees_3(3.0f);
+  vec4 a = tint_degrees(vec4(0.0f));
+  vec4 b = tint_degrees(vec4(1.0f));
+  vec4 c = tint_degrees(vec4(1.0f, 2.0f, 3.0f, 4.0f));
+  vec3 d = tint_degrees_1(vec3(0.0f));
+  vec3 e = tint_degrees_1(vec3(1.0f));
+  vec3 f = tint_degrees_1(vec3(1.0f, 2.0f, 3.0f));
+  vec2 g = tint_degrees_2(vec2(0.0f));
+  vec2 h = tint_degrees_2(vec2(1.0f));
+  vec2 i = tint_degrees_2(vec2(1.0f, 2.0f));
+  float j = tint_degrees_3(1.0f);
+  float k = tint_degrees_3(2.0f);
+  float l = tint_degrees_3(3.0f);
 }
 
 layout(local_size_x = 1, local_size_y = 1, local_size_z = 1) in;

test/tint/builtins/repeated_use.wgsl.expected.msl

@@ -19,18 +19,18 @@ float tint_degrees_3(float param_0) {
 }
 
 kernel void tint_symbol() {
-  tint_degrees(float4(0.0f));
-  tint_degrees(float4(1.0f));
-  tint_degrees(float4(1.0f, 2.0f, 3.0f, 4.0f));
-  tint_degrees_1(float3(0.0f));
-  tint_degrees_1(float3(1.0f));
-  tint_degrees_1(float3(1.0f, 2.0f, 3.0f));
-  tint_degrees_2(float2(0.0f));
-  tint_degrees_2(float2(1.0f));
-  tint_degrees_2(float2(1.0f, 2.0f));
-  tint_degrees_3(1.0f);
-  tint_degrees_3(2.0f);
-  tint_degrees_3(3.0f);
+  float4 const a = tint_degrees(float4(0.0f));
+  float4 const b = tint_degrees(float4(1.0f));
+  float4 const c = tint_degrees(float4(1.0f, 2.0f, 3.0f, 4.0f));
+  float3 const d = tint_degrees_1(float3(0.0f));
+  float3 const e = tint_degrees_1(float3(1.0f));
+  float3 const f = tint_degrees_1(float3(1.0f, 2.0f, 3.0f));
+  float2 const g = tint_degrees_2(float2(0.0f));
+  float2 const h = tint_degrees_2(float2(1.0f));
+  float2 const i = tint_degrees_2(float2(1.0f, 2.0f));
+  float const j = tint_degrees_3(1.0f);
+  float const k = tint_degrees_3(2.0f);
+  float const l = tint_degrees_3(3.0f);
   return;
 }
 

test/tint/builtins/repeated_use.wgsl.expected.wgsl

@@ -1,15 +1,15 @@
 @compute @workgroup_size(1)
 fn main() {
-  _ = degrees(vec4<f32>());
-  _ = degrees(vec4<f32>(1.0));
-  _ = degrees(vec4<f32>(1.0, 2.0, 3.0, 4.0));
-  _ = degrees(vec3<f32>());
-  _ = degrees(vec3<f32>(1.0));
-  _ = degrees(vec3<f32>(1.0, 2.0, 3.0));
-  _ = degrees(vec2<f32>());
-  _ = degrees(vec2<f32>(1.0));
-  _ = degrees(vec2<f32>(1.0, 2.0));
-  _ = degrees(1.0);
-  _ = degrees(2.0);
-  _ = degrees(3.0);
+  let a = degrees(vec4<f32>());
+  let b = degrees(vec4<f32>(1.0));
+  let c = degrees(vec4<f32>(1.0, 2.0, 3.0, 4.0));
+  let d = degrees(vec3<f32>());
+  let e = degrees(vec3<f32>(1.0));
+  let f = degrees(vec3<f32>(1.0, 2.0, 3.0));
+  let g = degrees(vec2<f32>());
+  let h = degrees(vec2<f32>(1.0));
+  let i = degrees(vec2<f32>(1.0, 2.0));
+  let j = degrees(1.0);
+  let k = degrees(2.0);
+  let l = degrees(3.0);
 }