[CSOptimizer] Allow matching against CGFloat as a contextual result type

lib/Sema/CSOptimizer.cpp

@@ -1056,19 +1056,6 @@ static void determineBestChoicesInContext(
           if (canUseContextualResultTypes() &&
               (score > 0 || !hasArgumentCandidates)) {
             if (llvm::any_of(resultTypes, [&](const Type candidateResultTy) {
-                  // Avoid increasing weight based on CGFloat result type
-                  // match because that could require narrowing conversion
-                  // in the arguments and that is always detrimental.
-                  //
-                  // For example, `has_CGFloat_param(1.0 + 2.0)` should use
-                  // `+(_: Double, _: Double) -> Double` instead of
-                  // `+(_: CGFloat, _: CGFloat) -> CGFloat` which would match
-                  // parameter of `has_CGFloat_param` exactly but use a
-                  // narrowing conversion for both literals.
-                  if (candidateResultTy->lookThroughAllOptionalTypes()
-                          ->isCGFloat())
-                    return false;
-
                   return scoreCandidateMatch(genericSig, decl,
                                              overloadType->getResult(),
                                              candidateResultTy,

validation-test/Sema/type_checker_perf/fast/complex_swiftui_padding_conditions.swift

@@ -1,4 +1,4 @@
-// RUN: %target-typecheck-verify-swift -target %target-cpu-apple-macosx10.15 -swift-version 5
+// RUN: %target-typecheck-verify-swift -target %target-cpu-apple-macosx10.15 -solver-scope-threshold=1000
 // REQUIRES: OS=macosx
 
 import SwiftUI

validation-test/Sema/type_checker_perf/fast/contextual_cgfloat_type_with_operator_chain_arguments.swift

@@ -0,0 +1,17 @@
+// RUN: %target-typecheck-verify-swift -solver-scope-threshold=50
+
+// REQUIRES: OS=macosx,no_asan
+// REQUIRES: objc_interop
+
+import Foundation
+
+struct Size {
+  var width: CGFloat
+  var height: CGFloat
+}
+
+func frame(width: CGFloat?, height: CGFloat?) {}
+
+func test(size: Size?) {
+  frame(width: ((size?.width ?? 0) * 1) + 1.0, height: ((size?.height ?? 0) * 1) + 1.0)
+}