Sure. I can try to whittle down the testcase that I'm working on. -bw
On Oct 2, 2007, at 8:35 PM, Chris Lattner wrote: > Hi Bill, > > This is not enough context to reproduce this issue. Can you please > include more in the .ll file? Specifically, the movswl wouldn't > exist if "tmp654" weren't live out I hope. It would be best if > the .ll fragments were actually compilable. > > -Chris > > On Oct 2, 2007, at 2:49 PM, Bill Wendling wrote: > >> Author: void >> Date: Tue Oct 2 16:49:31 2007 >> New Revision: 42554 >> >> URL: http://llvm.org/viewvc/llvm-project?rev=42554&view=rev >> Log: >> Another micro-opt. >> >> Modified: >> llvm/trunk/lib/Target/X86/README.txt >> >> Modified: llvm/trunk/lib/Target/X86/README.txt >> URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/lib/Target/X86/ >> README.txt?rev=42554&r1=42553&r2=42554&view=diff >> >> ===================================================================== >> = >> ======== >> --- llvm/trunk/lib/Target/X86/README.txt (original) >> +++ llvm/trunk/lib/Target/X86/README.txt Tue Oct 2 16:49:31 2007 >> @@ -1306,3 +1306,19 @@ >> movl 88(%esp), %eax >> #481.12 >> >> // >> ===------------------------------------------------------------------ >> - >> --===// >> + >> +This code: >> + >> + %tmp659 = icmp slt i16 %tmp654, 0 ; <i1> [#uses=1] >> + br i1 %tmp659, label %cond_true662, label %cond_next715 >> + >> +produces this: >> + >> + testw %cx, %cx >> + movswl %cx, %esi >> + jns LBB4_109 # cond_next715 >> + >> +Shark tells us that using %cx in the testw instruction is sub- >> optimal. It >> +suggests using the 32-bit register (which is what ICC uses). >> + >> +// >> ===------------------------------------------------------------------ >> - >> --===// >> >> >> _______________________________________________ >> llvm-commits mailing list >> llvm-commits@cs.uiuc.edu >> http://lists.cs.uiuc.edu/mailman/listinfo/llvm-commits > > _______________________________________________ > llvm-commits mailing list > llvm-commits@cs.uiuc.edu > http://lists.cs.uiuc.edu/mailman/listinfo/llvm-commits _______________________________________________ llvm-commits mailing list llvm-commits@cs.uiuc.edu http://lists.cs.uiuc.edu/mailman/listinfo/llvm-commits
