[llvm] [CGData] Declare command line options in TableGen, one struct per library (PR #226087)

[Alexis Engelke via llvm-commits]

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@@ -0,0 +1,51 @@
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+include "llvm/Option/OptParser.td"
+
+def CGDataOptions : OptionsStruct;
+
+defm CodeGenDataGenerate : BoolField<"codegen-data-generate", "false",
+  "Emit CodeGen Data into custom sections">;
+defm CodeGenDataThinLTOTwoRounds : BoolField<"codegen-data-thinlto-two-rounds",
+  "false", "Enable two-round ThinLTO code generation. The first round emits "
+  "codegen data, while the second round uses the emitted codegen data for "
+  "further optimizations.">;
+defm CodeGenDataUsePath : ValueField<"codegen-data-use-path", "StringRef",
+  "", "File path to where .cgdata file is read">;
+defm GlobalMergingCallOverhead : ValueField<"global-merging-call-overhead",
+  "double", "1.0", "The overhead cost associated with each function call when "
+  "merging functions.">;
+defm GlobalMergingExtraThreshold : ValueField<"global-merging-extra-threshold",
+  "double", "0.0", "An additional cost threshold that must be exceeded for "
+  "merging to be considered beneficial.">;
+defm GlobalMergingInstOverhead : ValueField<"global-merging-inst-overhead",
+  "double", "1.2", "The overhead cost associated with each instruction when "
+  "lowering to machine instruction.">;
+defm GlobalMergingMaxParams : ValueField<"global-merging-max-params",
+  "unsigned", "std::numeric_limits<unsigned>::max()",
+  "The maximum number of parameters allowed when merging functions.">;
+defm GlobalMergingMinInstrs : ValueField<"global-merging-min-instrs",
+  "unsigned", "1",
+  "The minimum instruction count required when merging functions.">;
+defm GlobalMergingMinMerges : ValueField<"global-merging-min-merges",
+  "unsigned", "2", "Minimum number of similar functions with the same hash "
+  "required for merging.">;
+defm GlobalMergingParamOverhead : ValueField<"global-merging-param-overhead",
+  "double", "2.0", "The overhead cost associated with each parameter when "
+  "merging functions.">;
+defm GlobalMergingSkipNoParams : BoolField<"global-merging-skip-no-params",
+  "true", "Skip merging functions with no parameters.">;
+defm IndexedCodeGenDataLazyLoading : BoolField<
+  "indexed-codegen-data-lazy-loading", "false", "Lazily load indexed "
+  "CodeGenData. Enable to save memory and time for final consumption of the "
+  "indexed CodeGenData in production.">;
+defm IndexedCodeGenDataReadFunctionMapNames : BoolField<
+  "indexed-codegen-data-read-function-map-names", "true", "Read function map "
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aengelke wrote:

Btw., can't we infer the dashed-option-name from the PascalCaseOptionName (or vice versa)? This is quite redundant currently (and if it weren't, that'd be not good, consistency is nice). Also something for later and something quite optional, though.

https://github.com/llvm/llvm-project/pull/226087