SimplifyCFG: Skip convert_escape_to_noescape in try_apply -> apply optimization

Author: aschwaighofer

lib/SILOptimizer/Transforms/SimplifyCFG.cpp

@@ -2004,6 +2004,10 @@ static SILValue getActualCallee(SILValue Callee) {
       Callee = CFI->getConverted();
       continue;
     }
+    if (auto *Cvt = dyn_cast<ConvertEscapeToNoEscapeInst>(Callee)) {
+      Callee = Cvt->getConverted();
+      continue;
+    }
     if (auto *TTI = dyn_cast<ThinToThickFunctionInst>(Callee)) {
       Callee = TTI->getConverted();
       continue;
@@ -2019,7 +2023,14 @@ static SILValue getActualCallee(SILValue Callee) {
 static bool isTryApplyOfConvertFunction(TryApplyInst *TAI,
                                               SILValue &Callee,
                                               SILType &CalleeType) {
-  auto *CFI = dyn_cast<ConvertFunctionInst>(TAI->getCallee());
+  auto CalleeOperand = TAI->getCallee();
+
+  // Look through a @noescape conversion.
+  auto *Cvt = dyn_cast<ConvertEscapeToNoEscapeInst>(CalleeOperand);
+  if (Cvt)
+    CalleeOperand = Cvt->getConverted();
+
+  auto *CFI = dyn_cast<ConvertFunctionInst>(CalleeOperand);
   if (!CFI)
     return false;
 

test/SILOptimizer/simplify_cfg.sil

@@ -3017,3 +3017,30 @@ bb9(%6 : $Builtin.Int32):
   return %6 : $Builtin.Int32
 }
 
+sil @adder : $@convention(thin) (Builtin.Int32, Builtin.Int32) -> Builtin.Int32
+
+// CHECK-LABEL: sil @test_noescape
+// CHECK:  [[FN:%.*]] = function_ref @adder
+// CHECK:  [[PA:%.*]] = partial_apply [callee_guaranteed] [[FN]](%0)
+// CHECK-NOT: try_apply
+// CHECK:  apply [[PA]](%1)
+// CHECK: return
+sil @test_noescape : $@convention(thin) (Builtin.Int32, Builtin.Int32) -> Builtin.Int32 {
+bb0(%0 : $Builtin.Int32, %1 : $Builtin.Int32):
+  %f = function_ref @adder : $@convention(thin) (Builtin.Int32, Builtin.Int32) -> Builtin.Int32
+  %pa = partial_apply [callee_guaranteed] %f(%0) : $@convention(thin) (Builtin.Int32, Builtin.Int32) -> Builtin.Int32
+  %conv = convert_function %pa : $@callee_guaranteed (Builtin.Int32) -> (Builtin.Int32) to $@callee_guaranteed (Builtin.Int32) -> (Builtin.Int32, @error Error)
+  %ne = convert_escape_to_noescape %conv : $@callee_guaranteed (Builtin.Int32) -> (Builtin.Int32, @error Error) to $@noescape @callee_guaranteed (Builtin.Int32) -> (Builtin.Int32, @error Error)
+  try_apply %ne(%1) : $@noescape @callee_guaranteed (Builtin.Int32) -> (Builtin.Int32, @error Error), normal bb1, error bb2
+
+bb1(%r : $Builtin.Int32):
+	br bb3(%r : $Builtin.Int32)
+
+bb2(%e : $Error):
+  %r1 = integer_literal $Builtin.Int32, 0
+	br bb3(%r1 : $Builtin.Int32)
+
+bb3(%res : $Builtin.Int32):
+  release_value %pa : $@callee_guaranteed (Builtin.Int32) -> (Builtin.Int32)
+  return  %res : $Builtin.Int32
+}