[clang][cas] Switch to include-tree by default

As of 3a924f2 we have significantly fewer known isuses with
include-tree caching than with cas-fs, so it's time to switch the
default.

rdar://107575958

Author: benlangmuir

clang/test/Index/Core/scan-deps-cas.m

@@ -1,26 +1,26 @@
-// RUN: rm -rf %t.mcp %t
+// RUN: rm -rf %t
 
 // RUN: c-index-test core --scan-deps %S -output-dir=%t -cas-path %t/cas \
 // RUN:  -- %clang -c -I %S/Inputs/module \
-// RUN:     -fmodules -fmodules-cache-path=%t.mcp \
+// RUN:     -fmodules -fmodules-cache-path=%t/mcpit \
 // RUN:     -o FoE.o -x objective-c %s > %t.result
-// RUN: cat %t.result | sed 's/\\/\//g' | FileCheck %s -DPREFIX=%S -DOUTPUTS=%/t
+// RUN: cat %t.result | sed 's/\\/\//g' | FileCheck %s -DPREFIX=%S -DOUTPUTS=%/t -check-prefix=INCLUDE_TREE
 
 // RUN: env CLANG_CACHE_USE_CASFS_DEPSCAN=1 c-index-test core --scan-deps %S -output-dir=%t -cas-path %t/cas \
 // RUN:  -- %clang -c -I %S/Inputs/module \
-// RUN:     -fmodules -fmodules-cache-path=%t.mcp \
+// RUN:     -fmodules -fmodules-cache-path=%t/mcp \
 // RUN:     -o FoE.o -x objective-c %s > %t.casfs.result
 // RUN: cat %t.casfs.result | sed 's/\\/\//g' | FileCheck %s -DPREFIX=%S -DOUTPUTS=%/t
 
-// FIXME: enable modules when supported.
 // RUN: env CLANG_CACHE_USE_INCLUDE_TREE=1 c-index-test core --scan-deps %S -output-dir=%t -cas-path %t/cas \
 // RUN:  -- %clang -c -I %S/Inputs/module \
+// RUN:     -fmodules -fmodules-cache-path=%t/mcpit \
 // RUN:     -o FoE.o -x objective-c %s > %t.includetree.result
 // RUN: cat %t.includetree.result | sed 's/\\/\//g' | FileCheck %s -DPREFIX=%S -DOUTPUTS=%/t -check-prefix=INCLUDE_TREE
 
 // RUN: c-index-test core --scan-deps %S -output-dir=%t \
 // RUN:  -- %clang -c -I %S/Inputs/module \
-// RUN:     -fmodules -fmodules-cache-path=%t.mcp \
+// RUN:     -fmodules -fmodules-cache-path=%t/mcp \
 // RUN:     -o FoE.o -x objective-c %s | FileCheck %s -check-prefix=NO_CAS
 // NO_CAS-NOT: fcas
 // NO_CAS-NOT: faction-cache
@@ -65,16 +65,37 @@
 // CHECK-SAME:       -fmodule-file-cache-key [[PCM:.*ModA_.*pcm]] llvmcas://{{[[:xdigit:]]+}}
 // CHECK-SAME:       -fmodule-file={{(ModA=)?}}[[PCM]]
 
+
+// INCLUDE_TREE:      modules:
+// INCLUDE_TREE-NEXT:   module:
+// INCLUDE_TREE-NEXT:     name: ModA
+// INCLUDE_TREE-NEXT:     context-hash: [[HASH_MOD_A:[A-Z0-9]+]]
+// INCLUDE_TREE-NEXT:     module-map-path: /Users/blangmuir/src/cas/llvm-project/clang/test/Index/Core/Inputs/module/module.modulemap
+// INCLUDE_TREE-NEXT:     cache-key: [[ModA_CACHE_KEY:llvmcas://[[:xdigit:]]+]]
+// INCLUDE_TREE-NEXT:     module-deps:
+// INCLUDE_TREE-NEXT:     file-deps:
+// INCLUDE_TREE-NEXT:       [[PREFIX]]/Inputs/module/ModA.h
+// INCLUDE_TREE-NEXT:       [[PREFIX]]/Inputs/module/SubModA.h
+// INCLUDE_TREE-NEXT:       [[PREFIX]]/Inputs/module/SubSubModA.h
+// INCLUDE_TREE-NEXT:       [[PREFIX]]/Inputs/module/module.modulemap
+// INCLUDE_TREE-NEXT:     build-args:
+// INCLUDE_TREE-SAME:       -cc1
+// INCLUDE_TREE-SAME:       -fcas-path
+// INCLUDE_TREE-SAME:       -fcas-include-tree llvmcas://{{[[:xdigit:]]+}}
+// INCLUDE_TREE-SAME:       -fcache-compile-job
+
 // INCLUDE_TREE:      dependencies:
 // INCLUDE_TREE-NEXT:   command 0:
 // INCLUDE_TREE-NEXT:     context-hash: [[HASH_TU:[A-Z0-9]+]]
 // INCLUDE_TREE-NEXT:     cache-key: [[INC_TU_CACHE_KEY:llvmcas://[[:xdigit:]]+]]
 // INCLUDE_TREE-NEXT:     module-deps:
+// INCLUDE_TREE-NEXT:       ModA:[[HASH_MOD_A]]
 // INCLUDE_TREE-NEXT:     file-deps:
 // INCLUDE_TREE-NEXT:       [[PREFIX]]/scan-deps-cas.m
-// INCLUDE_TREE-NEXT:       [[PREFIX]]/Inputs/module/ModA.h
 // INCLUDE_TREE-NEXT:     build-args:
 // INCLUDE_TREE-SAME:       -cc1
 // INCLUDE_TREE-SAME:       -fcas-path
 // INCLUDE_TREE-SAME:       -fcas-include-tree llvmcas://{{[[:xdigit:]]+}}
 // INCLUDE_TREE-SAME:       -fcache-compile-job
+// INCLUDE_TREE-SAME:       -fmodule-file-cache-key [[PCM:.*ModA_.*pcm]] [[ModA_CACHE_KEY]]
+// INCLUDE_TREE-SAME:       -fmodule-file={{(ModA=)?}}[[PCM]]

clang/tools/libclang/CDependencies.cpp

@@ -145,8 +145,8 @@ ScanningOutputFormat DependencyScannerServiceOptions::getFormat() const {
   if (llvm::sys::Process::GetEnv("CLANG_CACHE_USE_CASFS_DEPSCAN"))
     return ScanningOutputFormat::FullTree;
 
-  // Note: default caching behaviour is currently cas-fs.
-  return ScanningOutputFormat::FullTree;
+  // Use include-tree by default.
+  return ScanningOutputFormat::FullIncludeTree;
 }
 
 CXDependencyScannerService