commit 364c296101b258bd26a2410e1e58d64faacc0f0a
author Arnold Schwaighofer <aschwaighofer@apple.com> Fri Mar 23 12:22:38 2018 -0700
committer GitHub <noreply@github.com> Fri Mar 23 12:22:38 2018 -0700
tree 524941ce4be007bc79992738b5e7b851d64bedc7
parent 705a0bda639c2e5830905becb62541f4a9f07adb
parent 74f18ef11fbf05aa6caf98f2baa3778566add6c3

Merge pull request #15454 from aschwaighofer/irgen_fix_mem_attr_witness_table_accessor_conditional_conformance_4.1

[4.1] IRGen: Fix witness-table accessors for conditional conformances

lib/IRGen/GenProto.cpp

diff --git a/lib/IRGen/GenProto.cpp b/lib/IRGen/GenProto.cpp
index 902bcc7..49012e0 100644
--- a/lib/IRGen/GenProto.cpp
+++ b/lib/IRGen/GenProto.cpp
@@ -1064,6 +1064,7 @@
   // If the conformance is generic, the accessor takes the metatype plus
   // possible conditional conformances arguments.
   llvm::CallInst *call;
+  bool requiresMemoryArguments = false;
   if (conformance->witnessTableAccessorRequiresArguments()) {
     // Emit the source metadata if we haven't yet.
     if (!*srcMetadataCache) {
@@ -1076,13 +1077,14 @@
 
     call = IGF.Builder.CreateCall(
         accessor, {*srcMetadataCache, conditionalTables, numConditionalTables});
-
+    requiresMemoryArguments = true;
   } else {
     call = IGF.Builder.CreateCall(accessor, {});
   }
 
   call->setCallingConv(IGF.IGM.DefaultCC);
-  call->setDoesNotAccessMemory();
+  if (!requiresMemoryArguments)
+    call->setDoesNotAccessMemory();
   call->setDoesNotThrow();
 
   return call;

test/Inputs/conditional_conformance_basic_conformances.swift

diff --git a/test/Inputs/conditional_conformance_basic_conformances.swift b/test/Inputs/conditional_conformance_basic_conformances.swift
index 58f355e..748f547 100644
--- a/test/Inputs/conditional_conformance_basic_conformances.swift
+++ b/test/Inputs/conditional_conformance_basic_conformances.swift
@@ -102,7 +102,7 @@
 // CHECK-NEXT:    [[A_P2_PTR:%.*]] = getelementptr inbounds i8**, i8*** [[CONDITIONAL_REQUIREMENTS]], i32 0
 // CHECK-NEXT:    store i8** getelementptr inbounds ([0 x i8*], [0 x i8*]* @_T042conditional_conformance_basic_conformances4IsP2VAA0F0AAWP, i32 0, i32 0), i8*** [[A_P2_PTR]], align 8
 
-// CHECK-NEXT:    [[Single_P1:%.*]] = call i8** @_T042conditional_conformance_basic_conformances6SingleVyxGAA2P1A2A2P2RzlWa(%swift.type* [[Single_TYPE]], i8*** [[CONDITIONAL_REQUIREMENTS]], i64 1)
+// CHECK-NEXT:    [[Single_P1:%.*]] = call i8** @_T042conditional_conformance_basic_conformances6SingleVyxGAA2P1A2A2P2RzlWa(%swift.type* [[Single_TYPE]], i8*** [[CONDITIONAL_REQUIREMENTS]], i64 1) [[ATTRS:#[0-9]+]]
 // CHECK-NEXT:    store atomic i8** [[Single_P1]], i8*** @_T042conditional_conformance_basic_conformances6SingleVyAA4IsP2VGACyxGAA2P1A2A0G0RzlWL release, align 8
 // CHECK-NEXT:    br label %cont
 
@@ -323,3 +323,5 @@
 func dynamicCastToP1(_ value: Any) -> P1? {
   return value as? P1
 }
+
+// CHECK: attributes [[ATTRS]] = { nounwind }