7 Commits

Author SHA1 Message Date
Evan Cheng
51fa9c7138 Enable loop bb placement optimization.
llvm-svn: 71291
2009-05-08 23:35:49 +00:00
Evan Cheng
6e9959e327 Don't align loop header unless the loop back edge is below the header.
llvm-svn: 71242
2009-05-08 19:01:44 +00:00
Evan Cheng
5b9b33bcac Reverse branch condition only when there is a conditional branch.
llvm-svn: 71214
2009-05-08 09:35:53 +00:00
Nick Lewycky
b873ed672d Add explicit braces to disambiguate nested if/else. Removes a warning.
llvm-svn: 71211
2009-05-08 06:57:41 +00:00
Evan Cheng
2fa281106a Optimize code placement in loop to eliminate unconditional branches or move unconditional branch to the outside of the loop. e.g.
///       A:                                                                                                                                                                 
///       ...                                                                                                                                                                
///       <fallthrough to B>                                                                                                                                                 
///                                                                                                                                                                          
///       B:  --> loop header                                                                                                                                                
///       ...                                                                                                                                                                
///       jcc <cond> C, [exit]                                                                                                                                               
///                                                                                                                                                                          
///       C:                                                                                                                                                                 
///       ...                                                                                                                                                                
///       jmp B                                                                                                                                                              
///                                                                                                                                                                          
/// ==>                                                                                                                                                                      
///                                                                                                                                                                          
///       A:                                                                                                                                                                 
///       ...                                                                                                                                                                
///       jmp B                                                                                                                                                              
///                                                                                                                                                                          
///       C:  --> new loop header                                                                                                                                            
///       ...                                                                                                                                                                
///       <fallthough to B>                                                                                                                                                  
///                                                                                                                                                                          
///       B:                                                                                                                                                                 
///       ...                                                                                                                                                                
///       jcc <cond> C, [exit] 

llvm-svn: 71209
2009-05-08 06:34:09 +00:00
Evan Cheng
143bae5dcd Code refactoring.
llvm-svn: 71151
2009-05-07 05:49:39 +00:00
Evan Cheng
f356a89e92 Rename "loop aligner" pass to "code placement optimization" pass.
llvm-svn: 71150
2009-05-07 05:42:24 +00:00