Andrew Trick 57f0f255cf Allow CodeGen (llc) command line options to work as expected. ... The llc command line options for enabling/disabling passes are local to CodeGen/Passes.cpp. This patch associates those options with standard pass IDs so they work regardless of how the target configures the passes. A target has two ways of overriding standard passes: 1) Redefine the pass pipeline (override TargetPassConfig::add%Stage) 2) Replace or suppress individiual passes with TargetPassConfig::substitutePass. In both cases, the command line options associated with the pass override the target default. For example, say a target wants to disable machine instruction scheduling by default: - The target calls disablePass(MachineSchedulerID) but otherwise does not override any TargetPassConfig methods. - Without any llc options, no scheduler is run. - With -enable-misched, the standard machine scheduler is run and honors the -misched=... flag to select the scheduler variant, which may be used for performance evaluation or testing. Sorry overridePass is ugly. I haven't thought of a better way without replacing the cl::opt framework. I hope to do that one day... I haven't figured out why CodeGen uses char& for pass IDs. AnalysisID is much easier to use and less bug prone. I'm using it wherever I can for internal implementation. Maybe later we can change the global pass ID definitions as well. llvm-svn: 150563		2012-02-15 03:21:51 +00:00
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llvm	Allow CodeGen (llc) command line options to work as expected.	2012-02-15 03:21:51 +00:00
llvm-c	[unwind removal] Remove all of the code for the dead 'unwind' instruction. There	2012-02-06 21:44:22 +00:00