search for: loop_step

...gt; [#uses=1] br bool %matches9, label %ret_true, label %regex2 regex2: ; preds = %regex6 %c = load ubyte* %iter ; <ubyte> [#uses=1] %matches = seteq ubyte %c, 98 ; <bool> [#uses=1] br bool %matches, label %ret_true, label %loop_step loop_step: ; preds = %regex2 %next = getelementptr ubyte* %iter, int 1 ; <ubyte*> [#uses=1] br label %loop_test loop_test: ; preds = %loop_step, %entry %iter = phi ubyte* [ %begin, %entry ], [ %next, % loop_step ]...

...br bool %matches9, label %ret_true, label %regex2 > > regex2: ; preds = %regex6 > %c = load ubyte* %iter ; <ubyte> [#uses=1] > %matches = seteq ubyte %c, 98 ; <bool> [#uses=1] > br bool %matches, label %ret_true, label %loop_step > > loop_step: ; preds = %regex2 > %next = getelementptr ubyte* %iter, int 1 ; <ubyte*> > [#uses=1] > br label %loop_test > > loop_test: ; preds = %loop_step, %entry > %iter = phi ubyte* [ %begin, %entry ],...

...only are the loads eliminated, but the tests are actually reduced to a switch statement using '-anders-aa -load-vn -gcse -simplifycfg -instcombine': regex6: ; preds = %loop_test %c8 = load ubyte* %iter ; <ubyte> [#uses=1] switch ubyte %c8, label %loop_step [ ubyte 97, label %ret_true ubyte 98, label %ret_true ] Unfortunately, this generates really weird code on the LLVM 1.6 PowerPC backend: LBB_matches_1: ; regex6 lbz r4, 0(r3) LBB_matches_2: ; NodeBlock rlwinm r5, r4, 0, 24, 31...

...98 > beq cr0, LBB_matches_8 ; ret_true > b LBB_matches_5 ; NewDefault > LBB_matches_4: ; LeafBlock > rlwinm r4, r4, 0, 24, 31 > cmpwi cr0, r4, 97 > beq cr0, LBB_matches_8 ; ret_true > LBB_matches_5: ; NewDefault > LBB_matches_6: ; loop_step > > I'm particularly confused by the rlwinm instructions that keep > turning up in PowerPC output, and the double test against 98. I > don't have a problem or anything; I'm just trying to figure out > what's going on. :-) Ah! The backend is running -lowerswitch...