tint: uniformity: control flow reconverges after short-circuiting op when behaviour is {Next}
Bug: tint:1561
Change-Id: I685fe970f2c36d4ed39ba5fbe519736c031fbeca
Reviewed-on: https://dawn-review.googlesource.com/c/dawn/+/93160
Kokoro: Kokoro <noreply+kokoro@google.com>
Reviewed-by: James Price <jrprice@google.com>
Commit-Queue: Antonio Maiorano <amaiorano@google.com>
diff --git a/src/tint/resolver/uniformity.cc b/src/tint/resolver/uniformity.cc
index 6188521..97612a4 100644
--- a/src/tint/resolver/uniformity.cc
+++ b/src/tint/resolver/uniformity.cc
@@ -996,6 +996,10 @@
v1_cf->AddEdge(v1);
auto [cf2, v2] = ProcessExpression(v1_cf, b->rhs);
+
+ if (sem_.Get(b)->Behaviors() == sem::Behaviors{sem::Behavior::kNext}) {
+ return std::pair<Node*, Node*>(cf, v2);
+ }
return std::pair<Node*, Node*>(cf2, v2);
} else {
auto [cf1, v1] = ProcessExpression(cf, b->lhs);
diff --git a/src/tint/resolver/uniformity_test.cc b/src/tint/resolver/uniformity_test.cc
index 396baf8..7ed4a6b 100644
--- a/src/tint/resolver/uniformity_test.cc
+++ b/src/tint/resolver/uniformity_test.cc
@@ -5786,34 +5786,189 @@
)");
}
-TEST_F(UniformityAnalysisTest, ShortCircuiting_CausesNonUniformControlFlow) {
+TEST_F(UniformityAnalysisTest, ShortCircuiting_NoReconvergeLHS) {
std::string src = R"(
@group(0) @binding(0) var<storage, read_write> non_uniform_global : i32;
var<private> p : i32;
+fn non_uniform_discard_func() -> bool {
+ if (non_uniform_global == 42) {
+ discard;
+ }
+ return false;
+}
+
fn main() {
- let b = (non_uniform_global == 42) && false;
+ let b = non_uniform_discard_func() && false;
workgroupBarrier();
}
)";
RunTest(src, false);
EXPECT_EQ(error_,
- R"(test:8:3 warning: 'workgroupBarrier' must only be called from uniform control flow
+ R"(test:15:3 warning: 'workgroupBarrier' must only be called from uniform control flow
workgroupBarrier();
^^^^^^^^^^^^^^^^
-test:7:38 note: control flow depends on non-uniform value
- let b = (non_uniform_global == 42) && false;
- ^^
+test:14:11 note: calling 'non_uniform_discard_func' may cause subsequent control flow to be non-uniform
+ let b = non_uniform_discard_func() && false;
+ ^^^^^^^^^^^^^^^^^^^^^^^^
-test:7:12 note: reading from read_write storage buffer 'non_uniform_global' may result in a non-uniform value
- let b = (non_uniform_global == 42) && false;
- ^^^^^^^^^^^^^^^^^^
+test:7:3 note: control flow depends on non-uniform value
+ if (non_uniform_global == 42) {
+ ^^
+
+test:7:7 note: reading from read_write storage buffer 'non_uniform_global' may result in a non-uniform value
+ if (non_uniform_global == 42) {
+ ^^^^^^^^^^^^^^^^^^
)");
}
+TEST_F(UniformityAnalysisTest, ShortCircuiting_NoReconvergeRHS) {
+ std::string src = R"(
+@group(0) @binding(0) var<storage, read_write> non_uniform_global : i32;
+
+var<private> p : i32;
+
+fn non_uniform_discard_func() -> bool {
+ if (non_uniform_global == 42) {
+ discard;
+ }
+ return false;
+}
+
+fn main() {
+ let b = false && non_uniform_discard_func();
+ workgroupBarrier();
+}
+)";
+
+ RunTest(src, false);
+ EXPECT_EQ(error_,
+ R"(test:15:3 warning: 'workgroupBarrier' must only be called from uniform control flow
+ workgroupBarrier();
+ ^^^^^^^^^^^^^^^^
+
+test:14:20 note: calling 'non_uniform_discard_func' may cause subsequent control flow to be non-uniform
+ let b = false && non_uniform_discard_func();
+ ^^^^^^^^^^^^^^^^^^^^^^^^
+
+test:7:3 note: control flow depends on non-uniform value
+ if (non_uniform_global == 42) {
+ ^^
+
+test:7:7 note: reading from read_write storage buffer 'non_uniform_global' may result in a non-uniform value
+ if (non_uniform_global == 42) {
+ ^^^^^^^^^^^^^^^^^^
+)");
+}
+
+TEST_F(UniformityAnalysisTest, ShortCircuiting_NoReconvergeBoth) {
+ std::string src = R"(
+@group(0) @binding(0) var<storage, read_write> non_uniform_global : i32;
+
+var<private> p : i32;
+
+fn non_uniform_discard_func() -> bool {
+ if (non_uniform_global == 42) {
+ discard;
+ }
+ return false;
+}
+
+fn main() {
+ let b = non_uniform_discard_func() && non_uniform_discard_func();
+ workgroupBarrier();
+}
+)";
+
+ RunTest(src, false);
+ EXPECT_EQ(error_,
+ R"(test:15:3 warning: 'workgroupBarrier' must only be called from uniform control flow
+ workgroupBarrier();
+ ^^^^^^^^^^^^^^^^
+
+test:14:41 note: calling 'non_uniform_discard_func' may cause subsequent control flow to be non-uniform
+ let b = non_uniform_discard_func() && non_uniform_discard_func();
+ ^^^^^^^^^^^^^^^^^^^^^^^^
+
+test:7:3 note: control flow depends on non-uniform value
+ if (non_uniform_global == 42) {
+ ^^
+
+test:7:7 note: reading from read_write storage buffer 'non_uniform_global' may result in a non-uniform value
+ if (non_uniform_global == 42) {
+ ^^^^^^^^^^^^^^^^^^
+)");
+}
+
+TEST_F(UniformityAnalysisTest, ShortCircuiting_ReconvergeLHS) {
+ std::string src = R"(
+@group(0) @binding(0) var<storage, read_write> non_uniform_global : i32;
+
+var<private> p : i32;
+
+fn uniform_discard_func() -> bool {
+ if (true) {
+ discard;
+ }
+ return false;
+}
+
+fn main() {
+ let b = uniform_discard_func() && false;
+ workgroupBarrier();
+}
+)";
+
+ RunTest(src, true);
+}
+
+TEST_F(UniformityAnalysisTest, ShortCircuiting_ReconvergeRHS) {
+ std::string src = R"(
+@group(0) @binding(0) var<storage, read_write> non_uniform_global : i32;
+
+var<private> p : i32;
+
+fn uniform_discard_func() -> bool {
+ if (true) {
+ discard;
+ }
+ return false;
+}
+
+fn main() {
+ let b = false && uniform_discard_func();
+ workgroupBarrier();
+}
+)";
+
+ RunTest(src, true);
+}
+
+TEST_F(UniformityAnalysisTest, ShortCircuiting_ReconvergeBoth) {
+ std::string src = R"(
+@group(0) @binding(0) var<storage, read_write> non_uniform_global : i32;
+
+var<private> p : i32;
+
+fn uniform_discard_func() -> bool {
+ if (true) {
+ discard;
+ }
+ return false;
+}
+
+fn main() {
+ let b = uniform_discard_func() && uniform_discard_func();
+ workgroupBarrier();
+}
+)";
+
+ RunTest(src, true);
+}
+
TEST_F(UniformityAnalysisTest, DeadCode_AfterReturn) {
// Dead code after a return statement shouldn't cause uniformity errors.
std::string src = R"(
@@ -6228,8 +6383,15 @@
@group(0) @binding(0) var<uniform> uniform_value : i32;
@group(0) @binding(1) var<storage, read_write> non_uniform_value : i32;
+fn non_uniform_discard_func() -> bool {
+ if (non_uniform_value == 42) {
+ discard;
+ }
+ return false;
+}
+
fn main() {
- let b = (non_uniform_value == 0) && true;
+ let b = non_uniform_discard_func() && true;
if (uniform_value == 42) {
workgroupBarrier();
}
@@ -6238,17 +6400,21 @@
RunTest(src, false);
EXPECT_EQ(error_,
- R"(test:8:5 warning: 'workgroupBarrier' must only be called from uniform control flow
+ R"(test:15:5 warning: 'workgroupBarrier' must only be called from uniform control flow
workgroupBarrier();
^^^^^^^^^^^^^^^^
-test:6:36 note: control flow depends on non-uniform value
- let b = (non_uniform_value == 0) && true;
- ^^
+test:13:11 note: calling 'non_uniform_discard_func' may cause subsequent control flow to be non-uniform
+ let b = non_uniform_discard_func() && true;
+ ^^^^^^^^^^^^^^^^^^^^^^^^
-test:6:12 note: reading from read_write storage buffer 'non_uniform_value' may result in a non-uniform value
- let b = (non_uniform_value == 0) && true;
- ^^^^^^^^^^^^^^^^^
+test:6:3 note: control flow depends on non-uniform value
+ if (non_uniform_value == 42) {
+ ^^
+
+test:6:7 note: reading from read_write storage buffer 'non_uniform_value' may result in a non-uniform value
+ if (non_uniform_value == 42) {
+ ^^^^^^^^^^^^^^^^^
)");
}
