Changes

Summary

[llvm-elfabi] Add flag to preserve timestamp when output is the same (details)
Reland "[NewPM][CodeGen] Introduce CodeGenPassBuilder to help build codegen pipeline" (details)
[gn build] Port 21314940c48 (details)

Commit fddb41744958d21635a60622cfb4067122810bcc by haowei [llvm-elfabi] Add flag to preserve timestamp when output is the same This change adds '--write-if-changed' flag to llvm-elfabi tool. When enabled, llvm-elfabi will not overwrite the existing file if the content of the file will not be changed, which preserves the timestamp. Differential Revision: https://reviews.llvm.org/D92902
	llvm/test/tools/llvm-elfabi/preserve-dates-tbe.test
	llvm/test/tools/llvm-elfabi/preserve-dates-stub.test
	llvm/lib/InterfaceStub/ELFObjHandler.cpp
	llvm/tools/llvm-elfabi/llvm-elfabi.cpp
	llvm/include/llvm/InterfaceStub/ELFObjHandler.h
Commit 21314940c4856e0cb81b664fd2d2117d1b7dc3e3 by Yuanfang Chen Reland "[NewPM][CodeGen] Introduce CodeGenPassBuilder to help build codegen pipeline" This reverts commit 94427af60c66ffea655a3084825c6c3a9deec1ad (relands 4646de5d75cfce3da4ddeffb6eb8e66e38238800 with fix). Use "return std::move(AsmStreamer);" instead of "return AsmStreamer;" in LVMTargetMachine::createMCStreamer. Unlike Clang, GCC seems having trouble inserting a implicit lvalue->rvalue conversion.
	llvm/lib/CodeGen/CMakeLists.txt
	llvm/include/llvm/Target/CGPassBuilderOption.h
	llvm/lib/CodeGen/CodeGenPassBuilder.cpp
	llvm/include/llvm/CodeGen/MachinePassRegistry.def
	llvm/include/llvm/CodeGen/TargetPassConfig.h
	llvm/lib/CodeGen/TargetPassConfig.cpp
	llvm/include/llvm/CodeGen/CodeGenPassBuilder.h
	llvm/lib/CodeGen/LLVMTargetMachine.cpp
	llvm/include/llvm/Target/TargetMachine.h
Commit 92207b2ccea2c192be2aee32efe199dc682fd36f by llvmgnsyncbot [gn build] Port 21314940c48
	llvm/utils/gn/secondary/llvm/lib/CodeGen/BUILD.gn