Revert "[llvm] Preliminary fat-lto-objects support"

There seems to be a problem on arm buildbots. Reverting until I can
investigate.  https://lab.llvm.org/buildbot#builders/245/builds/10184

This reverts commit a67208e
and dependent commit e54a311.

Author: ilovepi

llvm/docs/FatLTO.rst

@@ -80,12 +80,6 @@ Changes to LLVM infrastructure
 * InstructionSimplify APIs now require instructions be inserted into a
   parent function.
 
-* A new FatLTO pipeline was added to support generating object files that have
-  both machine code and LTO compatible bitcode. See the :doc:`FatLTO`
-  documentation and the original
-  `RFC  <https://discourse.llvm.org/t/rfc-ffat-lto-objects-support/63977>`_
-  for more details.
-
 Changes to building LLVM
 ------------------------
 

llvm/docs/ReleaseNotes.rst

@@ -32,7 +32,6 @@ intermediate LLVM representation.
    DebuggingJITedCode
    DirectXUsage
    Docker
-   FatLTO
    ExtendingLLVM
    GoldPlugin
    HowToBuildOnARM

llvm/docs/UserGuides.rst

@@ -234,18 +234,6 @@ class PassBuilder {
   ModulePassManager buildPerModuleDefaultPipeline(OptimizationLevel Level,
                                                   bool LTOPreLink = false);
 
-  /// Build a fat object default optimization pipeline.
-  ///
-  /// This builds a pipeline that runs the LTO/ThinLTO  pre-link pipeline, and
-  /// emits a section containing the pre-link bitcode along side the object code
-  /// generated by running the PerModuleDefaultPipeline, used when compiling
-  /// without LTO. It clones the module and runs the LTO/non-LTO pipelines
-  /// separately to avoid any inconsistencies with an ad-hoc pipeline that tries
-  /// to approximate the PerModuleDefaultPipeline from the pre-link LTO
-  /// pipelines.
-  ModulePassManager buildFatLTODefaultPipeline(OptimizationLevel Level,
-                                               bool ThinLTO, bool EmitSummary);
-
   /// Build a pre-link, ThinLTO-targeting default optimization pipeline to
   /// a pass manager.
   ///

llvm/include/llvm/Passes/PassBuilder.h

@@ -79,7 +79,7 @@ uint32_t ObjectFile::getSymbolAlignment(DataRefImpl DRI) const { return 0; }
 bool ObjectFile::isSectionBitcode(DataRefImpl Sec) const {
   Expected<StringRef> NameOrErr = getSectionName(Sec);
   if (NameOrErr)
-    return *NameOrErr == ".llvmbc" || *NameOrErr == ".llvm.lto";
+    return *NameOrErr == ".llvmbc";
   consumeError(NameOrErr.takeError());
   return false;
 }

llvm/include/llvm/Transforms/IPO/EmbedBitcodePass.h

@@ -102,7 +102,6 @@
 #include "llvm/Transforms/IPO/CrossDSOCFI.h"
 #include "llvm/Transforms/IPO/DeadArgumentElimination.h"
 #include "llvm/Transforms/IPO/ElimAvailExtern.h"
-#include "llvm/Transforms/IPO/EmbedBitcodePass.h"
 #include "llvm/Transforms/IPO/ForceFunctionAttrs.h"
 #include "llvm/Transforms/IPO/FunctionAttrs.h"
 #include "llvm/Transforms/IPO/FunctionImport.h"
@@ -739,26 +738,6 @@ Expected<HWAddressSanitizerOptions> parseHWASanPassOptions(StringRef Params) {
   return Result;
 }
 
-Expected<EmbedBitcodeOptions> parseEmbedBitcodePassOptions(StringRef Params) {
-  EmbedBitcodeOptions Result;
-  while (!Params.empty()) {
-    StringRef ParamName;
-    std::tie(ParamName, Params) = Params.split(';');
-
-    if (ParamName == "thinlto") {
-      Result.IsThinLTO = true;
-    } else if (ParamName == "emit-summary") {
-      Result.EmitLTOSummary = true;
-    } else {
-      return make_error<StringError>(
-          formatv("invalid EmbedBitcode pass parameter '{0}' ", ParamName)
-              .str(),
-          inconvertibleErrorCode());
-    }
-  }
-  return Result;
-}
-
 Expected<MemorySanitizerOptions> parseMSanPassOptions(StringRef Params) {
   MemorySanitizerOptions Result;
   while (!Params.empty()) {

llvm/lib/Object/ObjectFile.cpp

@@ -46,7 +46,6 @@
 #include "llvm/Transforms/IPO/CrossDSOCFI.h"
 #include "llvm/Transforms/IPO/DeadArgumentElimination.h"
 #include "llvm/Transforms/IPO/ElimAvailExtern.h"
-#include "llvm/Transforms/IPO/EmbedBitcodePass.h"
 #include "llvm/Transforms/IPO/ForceFunctionAttrs.h"
 #include "llvm/Transforms/IPO/FunctionAttrs.h"
 #include "llvm/Transforms/IPO/GlobalDCE.h"
@@ -1465,18 +1464,7 @@ PassBuilder::buildPerModuleDefaultPipeline(OptimizationLevel Level,
 
   if (LTOPreLink)
     addRequiredLTOPreLinkPasses(MPM);
-  return MPM;
-}
 
-ModulePassManager
-PassBuilder::buildFatLTODefaultPipeline(OptimizationLevel Level, bool ThinLTO,
-                                        bool EmitSummary) {
-  ModulePassManager MPM;
-  MPM.addPass(EmbedBitcodePass(ThinLTO, EmitSummary,
-                               ThinLTO
-                                   ? buildThinLTOPreLinkDefaultPipeline(Level)
-                                   : buildLTOPreLinkDefaultPipeline(Level)));
-  MPM.addPass(buildPerModuleDefaultPipeline(Level));
   return MPM;
 }
 

llvm/lib/Passes/PassBuilder.cpp

@@ -170,13 +170,6 @@ MODULE_PASS_WITH_PARAMS("ipsccp",
                         },
                         parseIPSCCPOptions,
                         "no-func-spec;func-spec")
-MODULE_PASS_WITH_PARAMS("embed-bitcode",
-                         "EmbedBitcodePass",
-                        [](EmbedBitcodeOptions Opts) {
-                          return EmbedBitcodePass(Opts);
-                        },
-                        parseEmbedBitcodePassOptions,
-                        "thinlto;emit-summary")
 #undef MODULE_PASS_WITH_PARAMS
 
 #ifndef CGSCC_ANALYSIS

llvm/lib/Passes/PassBuilderPipelines.cpp

@@ -11,7 +11,6 @@ add_llvm_component_library(LLVMipo
   CrossDSOCFI.cpp
   DeadArgumentElimination.cpp
   ElimAvailExtern.cpp
-  EmbedBitcodePass.cpp
   ExtractGV.cpp
   ForceFunctionAttrs.cpp
   FunctionAttrs.cpp