[lld] [lld][ELF][MachO] rename to bp-* options for SectionOrderer (PR #118594)

[Ellis Hoag via llvm-commits]

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@@ -126,17 +126,21 @@ def no_call_graph_profile_sort : Flag<["--"], "no-call-graph-profile-sort">,
 def print_symbol_order_eq: Joined<["--"], "print-symbol-order=">,
     HelpText<"Print a symbol order specified by --call-graph-profile-sort into the specified file">,
     Group<grp_lld>;
+def irpgo_profile_eq: Joined<["--"], "irpgo-profile=">,
+    HelpText<"Read the IRPGO profile for use with -bp-startup-sort and other profile-guided optimizations">,
+    Group<grp_lld>;
+def bp_startup_sort: Joined<["--"], "bp-startup-sort=">,
+    MetaVarName<"[none,function]">,
+    HelpText<"Order sections based on profile data to improve startup time">,
+    Group<grp_lld>;
 def irpgo_profile_sort: Separate<["--"], "irpgo-profile-sort">, Group<grp_lld>;
 def irpgo_profile_sort_eq: Joined<["--"], "irpgo-profile-sort=">,
-    Alias<!cast<Separate>(irpgo_profile_sort)>, MetaVarName<"<profile>">,
-    HelpText<"Read the IRPGO profile at <profile> to order sections to improve startup time">,
-    Group<grp_lld>;
+    HelpText<"Deprecated. Please use --bp-startup-sort=function">, Group<grp_lld>;
 def compression_sort_startup_functions: Flag<["--"], "compression-sort-startup-functions">,
-    HelpText<"Order startup functions to improve compressed size in addition to startup time">,
-    Group<grp_lld>;
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ellishg wrote:

`-compression-sort-startup-functions` is a separate flag from `-bp-startup-sort=function`. This is saying that for the functions that we are ordering for startup, we also want to order them for compression. `-bp-startup-sort` is saying we want to order functions for startup. We should leave `compression_sort_startup_functions` alone for now, although I am open to different spellings, especially since we might order data for startup in the future.

https://github.com/llvm/llvm-project/pull/118594