[SILCombine] Handle indirect error in apply(conv).

Previously, only the indirect results and the parameters were handled.
However, the indirect error doesn't show up in the list of indirect
results (or in the list of parameters).  But it sure does show up in the
list of arguments.  Here, that argument too is handled.

rdar://127452206

Author: nate-chandler

lib/SILOptimizer/SILCombiner/SILCombinerApplyVisitors.cpp

@@ -157,6 +157,10 @@ SILCombiner::optimizeApplyOfConvertFunctionInst(FullApplySite AI,
   auto context = AI.getFunction()->getTypeExpansionContext();
   auto oldOpRetTypes = substConventions.getIndirectSILResultTypes(context);
   auto newOpRetTypes = convertConventions.getIndirectSILResultTypes(context);
+  auto oldIndirectErrorResultType =
+      substConventions.getIndirectErrorResultType(context);
+  auto newIndirectErrorResultType =
+      convertConventions.getIndirectErrorResultType(context);
   auto oldOpParamTypes = substConventions.getParameterSILTypes(context);
   auto newOpParamTypes = convertConventions.getParameterSILTypes(context);
 
@@ -186,7 +190,13 @@ SILCombiner::optimizeApplyOfConvertFunctionInst(FullApplySite AI,
        ++OpI, ++newRetI, ++oldRetI) {
     convertOp(Ops[OpI], *oldRetI, *newRetI);
   }
-  
+
+  if (oldIndirectErrorResultType) {
+    assert(newIndirectErrorResultType);
+    convertOp(Ops[OpI], oldIndirectErrorResultType, newIndirectErrorResultType);
+    ++OpI;
+  }
+
   auto newParamI = newOpParamTypes.begin();
   auto oldParamI = oldOpParamTypes.begin();
   for (auto e = newOpParamTypes.end(); newParamI != e;

test/SILOptimizer/sil_combine_apply_unit.sil

@@ -0,0 +1,34 @@
+// RUN: %target-sil-opt -enable-sil-verify-all %s -test-runner | %FileCheck %s
+
+import Builtin
+
+struct Input {}
+struct Output {}
+enum Nunca {}
+
+sil @rdar127452206_callee : $@convention(thin) @Sendable @substituted <τ_0_0, τ_0_1, τ_0_2> (@in_guaranteed τ_0_0) -> (@out τ_0_2, @error_indirect τ_0_1) for <Input, Nunca, Output>
+
+// CHECK-LABEL: sil @rdar127452206 : {{.*}} {
+// CHECK:       bb0([[INPUT:%[^,]+]] :
+// CHECK:         [[OUTPUT:%[^,]+]] = alloc_stack $Output
+// CHECK:         [[NUNCA:%[^,]+]] = alloc_stack $Nunca
+// CHECK:         [[OUTPUT_AS_OUTPUT:%[^,]+]] = unchecked_addr_cast [[OUTPUT]]
+// CHECK:         [[NUNCA_AS_NUNCA:%[^,]+]] = unchecked_addr_cast [[NUNCA]]
+// CHECK:         [[INPUT_AS_INPUT:%[^,]+]] = unchecked_addr_cast [[INPUT]]
+// CHECK:         apply [nothrow] {{%[^,]+}}([[OUTPUT_AS_OUTPUT]], [[NUNCA_AS_NUNCA]], [[INPUT_AS_INPUT]])
+// CHECK-LABEL: } // end sil function 'rdar127452206'
+sil @rdar127452206 : $@convention(thin) (@in Input) -> () {
+entry(%input : $*Input):
+  %output = alloc_stack $Output
+  %nunca = alloc_stack $Nunca
+  %callee = function_ref @rdar127452206_callee : $@convention(thin) @Sendable @substituted <τ_0_0, τ_0_1, τ_0_2> (@in_guaranteed τ_0_0) -> (@out τ_0_2, @error_indirect τ_0_1) for <Input, Nunca, Output>
+  %convert = convert_function %callee : $@convention(thin) @Sendable @substituted <τ_0_0, τ_0_1, τ_0_2> (@in_guaranteed τ_0_0) -> (@out τ_0_2, @error_indirect τ_0_1) for <Input, Nunca, Output> to $@convention(thin) @substituted <τ_0_0, τ_0_1, τ_0_2> (@in_guaranteed τ_0_0) -> (@out τ_0_2, @error_indirect τ_0_1) for <Input, Nunca, Output> // user: %216
+  specify_test "sil_combine_instruction @instruction[4]"
+  apply [nothrow] %convert(%output, %nunca, %input) : $@convention(thin) @substituted <τ_0_0, τ_0_1, τ_0_2> (@in_guaranteed τ_0_0) -> (@out τ_0_2, @error_indirect τ_0_1) for <Input, Nunca, Output>
+  dealloc_stack %nunca : $*Nunca
+  dealloc_stack %output : $*Output
+  %retval = tuple ()
+  return %retval : $()
+}
+
+