Fix LTO test to use just use libLTO.dylib

This is necessary until the Xcode toolchain's libLTO.dylib supports opaque pointers

Author: aschwaighofer

test/IRGen/hermetic-seal-exec.swift

@@ -3,7 +3,7 @@
 // RUN: %empty-directory(%t)
 
 // (1) Build library swiftmodule
-// RUN: %target-build-swift %s -DLIBRARY -module-name Library -experimental-hermetic-seal-at-link -lto=llvm-full %lto_flags \
+// RUN: %use_just_built_liblto %target-build-swift %s -DLIBRARY -module-name Library -experimental-hermetic-seal-at-link -lto=llvm-full %lto_flags \
 // RUN:     -Xfrontend -disable-reflection-metadata -Xfrontend -disable-reflection-names -Xfrontend -disable-objc-interop \
 // RUN:     -emit-library -static -o %t/libLibrary.a \
 // RUN:     -emit-module -emit-module-path %t/Library.swiftmodule
@@ -12,7 +12,7 @@
 // RUN: %llvm-nm %t/libLibrary.a | %FileCheck %s --check-prefix CHECK-NM-LIB
 
 // (3) Build client
-// RUN: %target-build-swift %s -DCLIENT -parse-as-library -module-name Main -experimental-hermetic-seal-at-link -lto=llvm-full %lto_flags \
+// RUN: %use_just_built_liblto %target-build-swift %s -DCLIENT -parse-as-library -module-name Main -experimental-hermetic-seal-at-link -lto=llvm-full %lto_flags \
 // RUN:     -Xfrontend -disable-reflection-metadata -Xfrontend -disable-reflection-names -Xfrontend -disable-objc-interop \
 // RUN:     -I%t -L%t -lLibrary -o %t/main
 // RUN: %target-codesign %t/main

test/IRGen/thinlto.swift

@@ -1,6 +1,6 @@
 // RUN: %empty-directory(%t)
-// RUN: %target-build-swift -parse-as-library -working-directory %t -lto=llvm-thin -DMODULE -static -emit-library -emit-module %s -module-name MyModule
-// RUN: %target-build-swift -parse-as-library -working-directory %t -lto=llvm-thin %s -I%t -L%t -lMyModule -module-name main -o %t/main %lto_flags
+// RUN: %use_just_built_liblto %target-build-swift -parse-as-library -working-directory %t -lto=llvm-thin -DMODULE -static -emit-library -emit-module %s -module-name MyModule
+// RUN: %use_just_built_liblto %target-build-swift -parse-as-library -working-directory %t -lto=llvm-thin %s -I%t -L%t -lMyModule -module-name main -o %t/main %lto_flags
 // RUN: %target-codesign %t/main
 // RUN: %target-run %t/main | %FileCheck %s
 

test/Interpreter/llvm_link_time_opt.swift

@@ -9,8 +9,8 @@
 // REQUIRES: no_asan
 
 // RUN: %empty-directory(%t)
-// RUN: %target-swiftc_driver -emit-library -static -lto=llvm-full %lto_flags -emit-module %S/Inputs/lto/module1.swift -working-directory %t
-// RUN: %target-swiftc_driver -lto=llvm-full %lto_flags %s -I%t -L%t -lmodule1 -module-name main -o %t/main
+// RUN: %use_just_built_liblto %target-swiftc_driver -emit-library -static -lto=llvm-full %lto_flags -emit-module %S/Inputs/lto/module1.swift -working-directory %t
+// RUN: %use_just_built_liblto %target-swiftc_driver -lto=llvm-full %lto_flags %s -I%t -L%t -lmodule1 -module-name main -o %t/main
 // RUN: %llvm-nm --defined-only %t/main | %FileCheck %s
 
 // CHECK-NOT: _$s7module120unusedPublicFunctionyyF

test/Interpreter/lto_static_lib.swift

@@ -1,7 +1,7 @@
 // RUN: %empty-directory(%t)
 // RUN: %target-build-swift -parse-as-library -lto=llvm-thin %s -emit-bc -o %t/a.o %lto_flags
-// RUN: ar -r -s %t/archive.a %t/a.o
-// RUN: %target-clang %t/archive.a -isysroot %sdk -L%swift-lib-dir/swift/%target-sdk-name -flto -o %t/main
+// RUN: %use_just_built_liblto ar -r -s %t/archive.a %t/a.o
+// RUN: %use_just_built_liblto %target-clang %t/archive.a -isysroot %sdk -L%swift-lib-dir/swift/%target-sdk-name -flto -o %t/main
 // RUN: %target-run %t/main | %FileCheck %s
 
 // REQUIRES: executable_test

test/lit.cfg

@@ -219,6 +219,7 @@ config.llvm_src_root = getattr(config, 'llvm_src_root', None)
 config.llvm_obj_root = getattr(config, 'llvm_obj_root', None)
 
 lto_flags = ""
+use_just_built_liblto = ""
 
 if platform.system() == 'OpenBSD':
     llvm_libs_dir = getattr(config, 'llvm_libs_dir', None)
@@ -231,8 +232,10 @@ elif platform.system() == 'Darwin':
     if not llvm_libs_dir:
         lit_config.fatal('No LLVM libs dir set.')
     lto_flags = "-Xlinker -lto_library -Xlinker %s/libLTO.dylib" % llvm_libs_dir
+    use_just_built_liblto = "LIBLTO_PATH=%s/libLTO.dylib" % llvm_libs_dir
 
 config.substitutions.append( ('%lto_flags', lto_flags) )
+config.substitutions.append( ('%use_just_built_liblto', use_just_built_liblto) )
 
 def append_to_env_path(directory):
     config.environment['PATH'] = \