[clang] [clang][modules] Track Included Files Per Submodule (PR #170215)

[Qiongsi Wu via cfe-commits]

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@@ -2373,10 +2386,8 @@ HeaderFileInfoTrait::ReadData(internal_key_ref key, const unsigned char *d,
     // implicit module import.
     SubmoduleID GlobalSMID = Reader.getGlobalSubmoduleID(M, LocalSMID);
     Module *Mod = Reader.getSubmodule(GlobalSMID);
-    ModuleMap &ModMap =
-        Reader.getPreprocessor().getHeaderSearchInfo().getModuleMap();
 
-    if (FE || (FE = getFile(key))) {
+    if (FE) {
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qiongsiwu wrote:

Are we commenting on the change where I removed the `FE = getFile(key)` expression? If so, I think we are ok because the expression seems loop invariant to me, and it is pulled out and is executed earlier unconditionally. See the change at [line 2356](https://github.com/llvm/llvm-project/pull/170215/files#diff-c61a3cce4bfa099b5af032fa83cbf1563f0af4bf58dc112b39571d74b6b681c1R2356). 

https://github.com/llvm/llvm-project/pull/170215