Merge pull request swiftlang#22657 from slavapestov/read-legacy-type-info-flag-fix

A couple of fixes for legacy type info support

Author: slavapestov

lib/IRGen/GenType.cpp

@@ -1151,23 +1151,28 @@ TypeConverter::TypeConverter(IRGenModule &IGM)
   if (IGM.IRGen.Opts.EnableResilienceBypass)
     LoweringMode = Mode::CompletelyFragile;
 
+  const auto &Triple = IGM.Context.LangOpts.Target;
+
   // We have a bunch of -parse-stdlib tests that pass a -target in the test
   // suite. To prevent these from failing when the user hasn't build the
   // standard library for that target, we pass -disable-legacy-type-info to
   // disable trying to load the legacy type info.
   if (IGM.IRGen.Opts.DisableLegacyTypeInfo)
     return;
 
-  auto platformName = getPlatformNameForTriple(IGM.Triple);
-  auto archName = getMajorArchitectureName(IGM.Triple);
-
-  if (!doesPlatformUseLegacyLayouts(platformName, archName))
-    return;
-
   llvm::SmallString<128> defaultPath;
 
   StringRef path = IGM.IRGen.Opts.ReadLegacyTypeInfoPath;
   if (path.empty()) {
+    // If the flag was not explicitly specified, look for a file in a
+    // platform-specific location, if this platform is known to require
+    // one.
+    auto platformName = getPlatformNameForTriple(Triple);
+    auto archName = swift::getMajorArchitectureName(Triple);
+
+    if (!doesPlatformUseLegacyLayouts(platformName, archName))
+      return;
+
     defaultPath.append(IGM.Context.SearchPathOpts.RuntimeLibraryPath);
     llvm::sys::path::append(defaultPath, "layouts-");
     defaultPath.append(archName);

test/IRGen/arm_to_thumb_darwin.sil

@@ -1,5 +1,5 @@
-// RUN: %swift -target armv7-apple-ios7 %s -gnone -emit-ir -o - | %FileCheck %s -check-prefix=IOS
-// RUN: %swift -target armv7k-apple-watchos2 %s -gnone -emit-ir -o - | %FileCheck %s -check-prefix=WATCHOS
+// RUN: %swift -target armv7-apple-ios7 -disable-legacy-type-info %s -gnone -emit-ir -o - | %FileCheck %s -check-prefix=IOS
+// RUN: %swift -target armv7k-apple-watchos2 -disable-legacy-type-info %s -gnone -emit-ir -o - | %FileCheck %s -check-prefix=WATCHOS
 
 // REQUIRES: CODEGENERATOR=ARM
 

test/IRGen/autorelease_optimized_armv7.sil

@@ -1,4 +1,4 @@
-// RUN: %swift -gnone -O -target armv7-apple-ios7 -emit-assembly %s -o - | %FileCheck %s
+// RUN: %swift -gnone -O -target armv7-apple-ios7 -disable-legacy-type-info -emit-assembly %s -o - | %FileCheck %s
 
 // REQUIRES: CODEGENERATOR=ARM
 

test/IRGen/bridge_object_armv7.sil

@@ -1,4 +1,4 @@
-// RUN: %swift -module-name bridge_object -emit-ir -target armv7-apple-ios8.0 %s | %FileCheck %s
+// RUN: %swift -module-name bridge_object -emit-ir -target armv7-apple-ios8.0 -disable-legacy-type-info %s | %FileCheck %s
 
 // REQUIRES: CODEGENERATOR=ARM
 

test/IRGen/integer_literal.sil

@@ -1,4 +1,4 @@
-// RUN: %swift -target armv7-apple-ios10 -module-name integer_literal %s -gnone -emit-ir | %FileCheck %s
+// RUN: %swift -target armv7-apple-ios10 -disable-legacy-type-info -module-name integer_literal %s -gnone -emit-ir | %FileCheck %s
 
 // REQUIRES: CODEGENERATOR=ARM
 

test/IRGen/ordering_arm.sil

@@ -1,4 +1,4 @@
-// RUN: %swift -target armv7-apple-ios7.1 %s -module-name main -emit-ir -o - | %FileCheck %s
+// RUN: %swift -target armv7-apple-ios7.1 -disable-legacy-type-info %s -module-name main -emit-ir -o - | %FileCheck %s
 
 // REQUIRES: CODEGENERATOR=ARM