[tfa] Propagate double constants

Similar to propagating `int` and `String` constants and literals,
propagate `double` constants and literals when they're not nan or
plus/minus zero.

Tested: updated existing test file with more cases
Change-Id: I1324a6804418710516c40c0744f0c5f417b92e83
Reviewed-on: https://dart-review.googlesource.com/c/sdk/+/405000
Reviewed-by: Martin Kustermann <[email protected]>
Commit-Queue: Ömer Ağacan <[email protected]>

Author: osa1

pkg/vm/lib/transformations/type_flow/summary_collector.dart

@@ -1588,9 +1588,19 @@ class SummaryCollector extends RecursiveResultVisitor<TypeExpr?> {
             ConstantExpression(constant: StringConstant()) => true,
             _ => false
           };
+      bool doubleIsSafeToPropagate(double d) => !d.isNaN && d != 0.0;
+      bool isDoubleConstantSafeToPropagate(Expression expr) => switch (expr) {
+            DoubleLiteral(value: var value) => doubleIsSafeToPropagate(value),
+            ConstantExpression(constant: DoubleConstant(value: var value)) =>
+              doubleIsSafeToPropagate(value),
+            _ => false
+          };
       if ((isIntConstant(rhs) &&
               _isSubtype(lhs.variable.type,
                   _environment.coreTypes.intNullableRawType)) ||
+          (isDoubleConstantSafeToPropagate(rhs) &&
+              _isSubtype(lhs.variable.type,
+                  _environment.coreTypes.doubleNullableRawType)) ||
           (isStringConstant(rhs) &&
               target.canInferStringClassAfterEqualityComparison &&
               _isSubtype(lhs.variable.type,

pkg/vm/testcases/transformations/type_flow/transformer/const_prop_conditional.dart

@@ -61,6 +61,30 @@ class OverriddenEq {
   String toString() => 'OverriddenEq(i=$i)';
 }
 
+void testDoubleLiteral1(double i) {
+  print(i);
+}
+
+void testDoubleLiteral2(double i) {
+  print(i);
+}
+
+void testDoubleLiteral3(double i) {
+  print(i);
+}
+
+void testDoubleConstant1(double i) {
+  print(i);
+}
+
+void testDoubleConstant2(double i) {
+  print(i);
+}
+
+void testDoubleConstant3(double i) {
+  print(i);
+}
+
 void main() {
   final s1 = runtimeTrue ? "foo" : "bar";
   if (s1 == "foo") {
@@ -101,4 +125,34 @@ void main() {
   if (c2 == sConst) {
     testOverriddenEq2(c2); // should not propagate
   }
+
+  final d1 = runtimeTrue ? 1.21 : 3.41;
+  if (d1 == 1.2) {
+    testDoubleLiteral1(d1); // should propagate
+  }
+
+  const d1Const = 12.34;
+  if (d1 == d1Const) {
+    testDoubleConstant1(d1); // should propagate
+  }
+
+  final d2 = runtimeTrue ? 1.34 : 5.67;
+  if (d2 == double.nan) {
+    testDoubleLiteral2(d2); // should not propagate
+  }
+
+  const d2Const = double.nan;
+  if (d2 == d2Const) {
+    testDoubleConstant2(d2); // should not propagate
+  }
+
+  final d3 = runtimeTrue ? 8.7 : 9.6;
+  if (d3 == -0.0) {
+    testDoubleLiteral3(d3); // should not propagate
+  }
+
+  const d3Const = -0.0;
+  if (d3 == d3Const) {
+    testDoubleConstant3(d3); // should not propagate
+  }
 }

pkg/vm/testcases/transformations/type_flow/transformer/const_prop_conditional.dart.expect

@@ -90,6 +90,40 @@ static method testOverriddenEq2([@vm.inferred-arg-type.metadata=#lib::Overridden
 static get runtimeTrue() → core::bool
   return [@vm.direct-call.metadata=dart.core::_IntegerImplementation.==] [@vm.inferred-type.metadata=dart.core::bool (skip check)] [@vm.inferred-type.metadata=int] core::int::parse("1") =={core::num::==}{(core::Object) → core::bool} 1;
 
+[@vm.inferred-return-type.metadata=dart.core::Null? (value: null)]
+static method testDoubleLiteral1() → void {
+  core::print(#C7);
+}
+
+[@vm.inferred-return-type.metadata=dart.core::Null? (value: null)]
+[@vm.unboxing-info.metadata=(d)->b]
+static method testDoubleLiteral2([@vm.inferred-arg-type.metadata=dart.core::_Double] core::double i) → void {
+  core::print(i);
+}
+
+[@vm.inferred-return-type.metadata=dart.core::Null? (value: null)]
+[@vm.unboxing-info.metadata=(d)->b]
+static method testDoubleLiteral3([@vm.inferred-arg-type.metadata=dart.core::_Double] core::double i) → void {
+  core::print(i);
+}
+
+[@vm.inferred-return-type.metadata=dart.core::Null? (value: null)]
+static method testDoubleConstant1() → void {
+  core::print(#C8);
+}
+
+[@vm.inferred-return-type.metadata=dart.core::Null? (value: null)]
+[@vm.unboxing-info.metadata=(d)->b]
+static method testDoubleConstant2([@vm.inferred-arg-type.metadata=dart.core::_Double] core::double i) → void {
+  core::print(i);
+}
+
+[@vm.inferred-return-type.metadata=dart.core::Null? (value: null)]
+[@vm.unboxing-info.metadata=(d)->b]
+static method testDoubleConstant3([@vm.inferred-arg-type.metadata=dart.core::_Double] core::double i) → void {
+  core::print(i);
+}
+
 [@vm.inferred-return-type.metadata=dart.core::Null? (value: null)]
 static method main() → void {
   final core::String s1 = [@vm.inferred-type.metadata=dart.core::bool] self::runtimeTrue ?{core::String} "foo" : "bar";
@@ -116,12 +150,33 @@ static method main() → void {
     self::testDefaultEq2();
   }
   final self::OverriddenEq c2 = [@vm.inferred-type.metadata=dart.core::bool] self::runtimeTrue ?{self::OverriddenEq} new self::OverriddenEq::•(1) : new self::OverriddenEq::•(2);
-  if([@vm.direct-call.metadata=#lib::OverriddenEq.==] [@vm.inferred-type.metadata=dart.core::bool (skip check) (receiver not int)] c2 =={self::OverriddenEq::==}{(core::Object) → core::bool} #C7) {
+  if([@vm.direct-call.metadata=#lib::OverriddenEq.==] [@vm.inferred-type.metadata=dart.core::bool (skip check) (receiver not int)] c2 =={self::OverriddenEq::==}{(core::Object) → core::bool} #C9) {
     self::testOverriddenEq1(c2);
   }
   if([@vm.direct-call.metadata=#lib::OverriddenEq.==] [@vm.inferred-type.metadata=dart.core::bool (skip check) (receiver not int)] c2 =={self::OverriddenEq::==}{(core::Object) → core::bool} #C2) {
     self::testOverriddenEq2(c2);
   }
+  final core::double d1 = [@vm.inferred-type.metadata=dart.core::bool] self::runtimeTrue ?{core::double} 1.21 : 3.41;
+  if([@vm.direct-call.metadata=dart.core::_Double.==] [@vm.inferred-type.metadata=dart.core::bool (skip check) (receiver not int)] d1 =={core::num::==}{(core::Object) → core::bool} 1.2) {
+    self::testDoubleLiteral1();
+  }
+  if([@vm.direct-call.metadata=dart.core::_Double.==] [@vm.inferred-type.metadata=dart.core::bool (skip check) (receiver not int)] d1 =={core::num::==}{(core::Object) → core::bool} #C8) {
+    self::testDoubleConstant1();
+  }
+  final core::double d2 = [@vm.inferred-type.metadata=dart.core::bool] self::runtimeTrue ?{core::double} 1.34 : 5.67;
+  if([@vm.direct-call.metadata=dart.core::_Double.==] [@vm.inferred-type.metadata=dart.core::bool (skip check) (receiver not int)] d2 =={core::num::==}{(core::Object) → core::bool} #C10) {
+    self::testDoubleLiteral2(d2);
+  }
+  if([@vm.direct-call.metadata=dart.core::_Double.==] [@vm.inferred-type.metadata=dart.core::bool (skip check) (receiver not int)] d2 =={core::num::==}{(core::Object) → core::bool} #C10) {
+    self::testDoubleConstant2(d2);
+  }
+  final core::double d3 = [@vm.inferred-type.metadata=dart.core::bool] self::runtimeTrue ?{core::double} 8.7 : 9.6;
+  if([@vm.direct-call.metadata=dart.core::_Double.==] [@vm.inferred-type.metadata=dart.core::bool (skip check) (receiver not int)] d3 =={core::num::==}{(core::Object) → core::bool} [@vm.direct-call.metadata=dart.core::_Double.unary-] [@vm.inferred-type.metadata=dart.core::_Double (skip check)] 0.0.{core::double::unary-}(){() → core::double}) {
+    self::testDoubleLiteral3(d3);
+  }
+  if([@vm.direct-call.metadata=dart.core::_Double.==] [@vm.inferred-type.metadata=dart.core::bool (skip check) (receiver not int)] d3 =={core::num::==}{(core::Object) → core::bool} #C11) {
+    self::testDoubleConstant3(d3);
+  }
 }
 constants  {
   #C1 = "foo"
@@ -130,5 +185,9 @@ constants  {
   #C4 = 456
   #C5 = 1
   #C6 = self::DefaultEq {i:#C5}
-  #C7 = self::OverriddenEq {i:#C5}
+  #C7 = 1.2
+  #C8 = 12.34
+  #C9 = self::OverriddenEq {i:#C5}
+  #C10 = NaN
+  #C11 = -0.0
 }