1 ; RUN: llc -mtriple=i686-linux -enable-block-placement < %s | FileCheck %s
3 declare void @error(i32 %i, i32 %a, i32 %b)
5 define i32 @test_ifchains(i32 %i, i32* %a, i32 %b) {
6 ; Test a chain of ifs, where the block guarded by the if is error handling code
7 ; that is not expected to run.
8 ; CHECK: test_ifchains:
22 %gep1 = getelementptr i32* %a, i32 1
23 %val1 = load i32* %gep1
24 %cond1 = icmp ugt i32 %val1, 1
25 br i1 %cond1, label %then1, label %else1, !prof !0
28 call void @error(i32 %i, i32 1, i32 %b)
32 %gep2 = getelementptr i32* %a, i32 2
33 %val2 = load i32* %gep2
34 %cond2 = icmp ugt i32 %val2, 2
35 br i1 %cond2, label %then2, label %else2, !prof !0
38 call void @error(i32 %i, i32 1, i32 %b)
42 %gep3 = getelementptr i32* %a, i32 3
43 %val3 = load i32* %gep3
44 %cond3 = icmp ugt i32 %val3, 3
45 br i1 %cond3, label %then3, label %else3, !prof !0
48 call void @error(i32 %i, i32 1, i32 %b)
52 %gep4 = getelementptr i32* %a, i32 4
53 %val4 = load i32* %gep4
54 %cond4 = icmp ugt i32 %val4, 4
55 br i1 %cond4, label %then4, label %else4, !prof !0
58 call void @error(i32 %i, i32 1, i32 %b)
62 %gep5 = getelementptr i32* %a, i32 3
63 %val5 = load i32* %gep5
64 %cond5 = icmp ugt i32 %val5, 3
65 br i1 %cond5, label %then5, label %exit, !prof !0
68 call void @error(i32 %i, i32 1, i32 %b)
75 define i32 @test_loop_cold_blocks(i32 %i, i32* %a) {
76 ; Check that we sink cold loop blocks after the hot loop body.
77 ; CHECK: test_loop_cold_blocks:
90 %iv = phi i32 [ 0, %entry ], [ %next, %body3 ]
91 %base = phi i32 [ 0, %entry ], [ %sum, %body3 ]
92 %unlikelycond1 = icmp slt i32 %base, 42
93 br i1 %unlikelycond1, label %unlikely1, label %body2, !prof !0
96 call void @error(i32 %i, i32 1, i32 %base)
100 %unlikelycond2 = icmp sgt i32 %base, 21
101 br i1 %unlikelycond2, label %unlikely2, label %body3, !prof !0
104 call void @error(i32 %i, i32 2, i32 %base)
108 %arrayidx = getelementptr inbounds i32* %a, i32 %iv
109 %0 = load i32* %arrayidx
110 %sum = add nsw i32 %0, %base
111 %next = add i32 %iv, 1
112 %exitcond = icmp eq i32 %next, %i
113 br i1 %exitcond, label %exit, label %body1
119 !0 = metadata !{metadata !"branch_weights", i32 4, i32 64}
121 define i32 @test_loop_early_exits(i32 %i, i32* %a) {
122 ; Check that we sink early exit blocks out of loop bodies.
123 ; CHECK: test_loop_early_exits:
138 %iv = phi i32 [ 0, %entry ], [ %next, %body4 ]
139 %base = phi i32 [ 0, %entry ], [ %sum, %body4 ]
140 %bailcond1 = icmp eq i32 %base, 42
141 br i1 %bailcond1, label %bail1, label %body2
147 %bailcond2 = icmp eq i32 %base, 43
148 br i1 %bailcond2, label %bail2, label %body3
154 %bailcond3 = icmp eq i32 %base, 44
155 br i1 %bailcond3, label %bail3, label %body4
161 %arrayidx = getelementptr inbounds i32* %a, i32 %iv
162 %0 = load i32* %arrayidx
163 %sum = add nsw i32 %0, %base
164 %next = add i32 %iv, 1
165 %exitcond = icmp eq i32 %next, %i
166 br i1 %exitcond, label %exit, label %body1
172 define i32 @test_loop_rotate(i32 %i, i32* %a) {
173 ; Check that we rotate conditional exits from the loop to the bottom of the
174 ; loop, eliminating unconditional branches to the top.
175 ; CHECK: test_loop_rotate:
185 %iv = phi i32 [ 0, %entry ], [ %next, %body1 ]
186 %base = phi i32 [ 0, %entry ], [ %sum, %body1 ]
187 %next = add i32 %iv, 1
188 %exitcond = icmp eq i32 %next, %i
189 br i1 %exitcond, label %exit, label %body1
192 %arrayidx = getelementptr inbounds i32* %a, i32 %iv
193 %0 = load i32* %arrayidx
194 %sum = add nsw i32 %0, %base
195 %bailcond1 = icmp eq i32 %sum, 42
202 define i32 @test_loop_align(i32 %i, i32* %a) {
203 ; Check that we provide basic loop body alignment with the block placement
205 ; CHECK: test_loop_align:
207 ; CHECK: .align [[ALIGN:[0-9]+]],
215 %iv = phi i32 [ 0, %entry ], [ %next, %body ]
216 %base = phi i32 [ 0, %entry ], [ %sum, %body ]
217 %arrayidx = getelementptr inbounds i32* %a, i32 %iv
218 %0 = load i32* %arrayidx
219 %sum = add nsw i32 %0, %base
220 %next = add i32 %iv, 1
221 %exitcond = icmp eq i32 %next, %i
222 br i1 %exitcond, label %exit, label %body
228 define i32 @test_nested_loop_align(i32 %i, i32* %a, i32* %b) {
229 ; Check that we provide nested loop body alignment.
230 ; CHECK: test_nested_loop_align:
232 ; CHECK: .align [[ALIGN]],
233 ; CHECK-NEXT: %loop.body.1
234 ; CHECK: .align [[ALIGN]],
235 ; CHECK-NEXT: %inner.loop.body
240 br label %loop.body.1
243 %iv = phi i32 [ 0, %entry ], [ %next, %loop.body.2 ]
244 %arrayidx = getelementptr inbounds i32* %a, i32 %iv
245 %bidx = load i32* %arrayidx
246 br label %inner.loop.body
249 %inner.iv = phi i32 [ 0, %loop.body.1 ], [ %inner.next, %inner.loop.body ]
250 %base = phi i32 [ 0, %loop.body.1 ], [ %sum, %inner.loop.body ]
251 %scaled_idx = mul i32 %bidx, %iv
252 %inner.arrayidx = getelementptr inbounds i32* %b, i32 %scaled_idx
253 %0 = load i32* %inner.arrayidx
254 %sum = add nsw i32 %0, %base
255 %inner.next = add i32 %iv, 1
256 %inner.exitcond = icmp eq i32 %inner.next, %i
257 br i1 %inner.exitcond, label %loop.body.2, label %inner.loop.body
260 %next = add i32 %iv, 1
261 %exitcond = icmp eq i32 %next, %i
262 br i1 %exitcond, label %exit, label %loop.body.1
268 define void @unnatural_cfg1() {
269 ; Test that we can handle a loop with an inner unnatural loop at the end of
270 ; a function. This is a gross CFG reduced out of the single source GCC.
271 ; CHECK: unnatural_cfg1
278 br label %loop.header
284 br i1 undef, label %loop.body3, label %loop.body2
287 %ptr = load i32** undef, align 4
291 %myptr = phi i32* [ %ptr2, %loop.body5 ], [ %ptr, %loop.body2 ], [ undef, %loop.body1 ]
292 %bcmyptr = bitcast i32* %myptr to i32*
293 %val = load i32* %bcmyptr, align 4
294 %comp = icmp eq i32 %val, 48
295 br i1 %comp, label %loop.body4, label %loop.body5
298 br i1 undef, label %loop.header, label %loop.body5
301 %ptr2 = load i32** undef, align 4
305 define void @unnatural_cfg2() {
306 ; Test that we can handle a loop with a nested natural loop *and* an unnatural
307 ; loop. This was reduced from a crash on block placement when run over
309 ; CHECK: unnatural_cfg2
311 ; CHECK: %loop.header
315 ; CHECK: %loop.inner1.begin
316 ; The end block is folded with %loop.body3...
317 ; CHECK-NOT: %loop.inner1.end
319 ; CHECK: %loop.inner2.begin
320 ; The loop.inner2.end block is folded
324 br label %loop.header
327 %comp0 = icmp eq i32* undef, null
328 br i1 %comp0, label %bail, label %loop.body1
331 %val0 = load i32** undef, align 4
332 br i1 undef, label %loop.body2, label %loop.inner1.begin
335 br i1 undef, label %loop.body4, label %loop.body3
338 %ptr1 = getelementptr inbounds i32* %val0, i32 0
339 %castptr1 = bitcast i32* %ptr1 to i32**
340 %val1 = load i32** %castptr1, align 4
341 br label %loop.inner1.begin
344 %valphi = phi i32* [ %val2, %loop.inner1.end ], [ %val1, %loop.body3 ], [ %val0, %loop.body1 ]
345 %castval = bitcast i32* %valphi to i32*
346 %comp1 = icmp eq i32 undef, 48
347 br i1 %comp1, label %loop.inner1.end, label %loop.body4
350 %ptr2 = getelementptr inbounds i32* %valphi, i32 0
351 %castptr2 = bitcast i32* %ptr2 to i32**
352 %val2 = load i32** %castptr2, align 4
353 br label %loop.inner1.begin
359 %comp2 = icmp ult i32 undef, 3
360 br i1 %comp2, label %loop.inner2.begin, label %loop.end
363 br i1 false, label %loop.end, label %loop.inner2.end
366 %comp3 = icmp eq i32 undef, 1769472
367 br i1 %comp3, label %loop.end, label %loop.inner2.begin
370 br label %loop.header
376 define i32 @problematic_switch() {
377 ; This function's CFG caused overlow in the machine branch probability
378 ; calculation, triggering asserts. Make sure we don't crash on it.
379 ; CHECK: problematic_switch
382 switch i32 undef, label %exit [
383 i32 879, label %bogus
423 %merge = phi i32 [ 3, %step ], [ 6, %entry ]
427 define void @fpcmp_unanalyzable_branch(i1 %cond) {
428 ; This function's CFG contains an unanalyzable branch that is likely to be
429 ; split due to having a different high-probability predecessor.
430 ; CHECK: fpcmp_unanalyzable_branch
433 ; CHECK-NOT: %if.then
439 ; CHECK-NEXT: %if.then
442 ; Note that this branch must be strongly biased toward
443 ; 'entry.if.then_crit_edge' to ensure that we would try to form a chain for
444 ; 'entry' -> 'entry.if.then_crit_edge' -> 'if.then'. It is the last edge in that
445 ; chain which would violate the unanalyzable branch in 'exit', but we won't even
446 ; try this trick unless 'if.then' is believed to almost always be reached from
447 ; 'entry.if.then_crit_edge'.
448 br i1 %cond, label %entry.if.then_crit_edge, label %lor.lhs.false, !prof !1
450 entry.if.then_crit_edge:
451 %.pre14 = load i8* undef, align 1, !tbaa !0
455 br i1 undef, label %if.end, label %exit
458 %cmp.i = fcmp une double 0.000000e+00, undef
459 br i1 %cmp.i, label %if.then, label %if.end
462 %0 = phi i8 [ %.pre14, %entry.if.then_crit_edge ], [ undef, %exit ]
464 store i8 %1, i8* undef, align 4, !tbaa !0
471 !1 = metadata !{metadata !"branch_weights", i32 1000, i32 1}
475 declare i32 @h(i32 %x)
477 define i32 @test_global_cfg_break_profitability() {
478 ; Check that our metrics for the profitability of a CFG break are global rather
479 ; than local. A successor may be very hot, but if the current block isn't, it
480 ; doesn't matter. Within this test the 'then' block is slightly warmer than the
481 ; 'else' block, but not nearly enough to merit merging it with the exit block
482 ; even though the probability of 'then' branching to the 'exit' block is very
484 ; CHECK: test_global_cfg_break_profitability
485 ; CHECK: calll {{_?}}f
486 ; CHECK: calll {{_?}}g
487 ; CHECK: calll {{_?}}h
491 br i1 undef, label %then, label %else, !prof !2
494 %then.result = call i32 @f()
498 %else.result = call i32 @g()
502 %result = phi i32 [ %then.result, %then ], [ %else.result, %else ]
503 %result2 = call i32 @h(i32 %result)
507 !2 = metadata !{metadata !"branch_weights", i32 3, i32 1}
509 declare i32 @__gxx_personality_v0(...)
511 define void @test_eh_lpad_successor() {
512 ; Some times the landing pad ends up as the first successor of an invoke block.
513 ; When this happens, a strange result used to fall out of updateTerminators: we
514 ; didn't correctly locate the fallthrough successor, assuming blindly that the
515 ; first one was the fallthrough successor. As a result, we would add an
516 ; erroneous jump to the landing pad thinking *that* was the default successor.
517 ; CHECK: test_eh_lpad_successor
523 invoke i32 @f() to label %preheader unwind label %lpad
529 %lpad.val = landingpad { i8*, i32 } personality i8* bitcast (i32 (...)* @__gxx_personality_v0 to i8*)
531 resume { i8*, i32 } %lpad.val
537 declare void @fake_throw() noreturn
539 define void @test_eh_throw() {
540 ; For blocks containing a 'throw' (or similar functionality), we have
541 ; a no-return invoke. In this case, only EH successors will exist, and
542 ; fallthrough simply won't occur. Make sure we don't crash trying to update
543 ; terminators for such constructs.
545 ; CHECK: test_eh_throw
550 invoke void @fake_throw() to label %continue unwind label %cleanup
556 %0 = landingpad { i8*, i32 } personality i8* bitcast (i32 (...)* @__gxx_personality_v0 to i8*)
561 define void @test_unnatural_cfg_backwards_inner_loop() {
562 ; Test that when we encounter an unnatural CFG structure after having formed
563 ; a chain for an inner loop which happened to be laid out backwards we don't
564 ; attempt to merge onto the wrong end of the inner loop just because we find it
565 ; first. This was reduced from a crasher in GCC's single source.
567 ; CHECK: test_unnatural_cfg_backwards_inner_loop
575 br i1 undef, label %loop2a, label %body
581 %next.load = load i32** undef
582 br i1 %comp.a, label %loop2a, label %loop2b
585 %var = phi i32* [ null, %entry ], [ null, %body ], [ %next.phi, %loop1 ]
586 %next.var = phi i32* [ null, %entry ], [ undef, %body ], [ %next.load, %loop1 ]
587 %comp.a = icmp eq i32* %var, null
591 %gep = getelementptr inbounds i32* %var.phi, i32 0
592 %next.ptr = bitcast i32* %gep to i32**
593 store i32* %next.phi, i32** %next.ptr
597 %var.phi = phi i32* [ %next.phi, %loop2b ], [ %var, %loop2a ]
598 %next.phi = phi i32* [ %next.load, %loop2b ], [ %next.var, %loop2a ]
602 define void @unanalyzable_branch_to_loop_header() {
603 ; Ensure that we can handle unanalyzable branches into loop headers. We
604 ; pre-form chains for unanalyzable branches, and will find the tail end of that
605 ; at the start of the loop. This function uses floating point comparison
606 ; fallthrough because that happens to always produce unanalyzable branches on
609 ; CHECK: unanalyzable_branch_to_loop_header
615 %cmp = fcmp une double 0.000000e+00, undef
616 br i1 %cmp, label %loop, label %exit
619 %cond = icmp eq i8 undef, 42
620 br i1 %cond, label %exit, label %loop
626 define void @unanalyzable_branch_to_best_succ(i1 %cond) {
627 ; Ensure that we can handle unanalyzable branches where the destination block
628 ; gets selected as the optimal sucessor to merge.
630 ; CHECK: unanalyzable_branch_to_best_succ
637 ; Bias this branch toward bar to ensure we form that chain.
638 br i1 %cond, label %bar, label %foo, !prof !1
641 %cmp = fcmp une double 0.000000e+00, undef
642 br i1 %cmp, label %bar, label %exit
652 define void @unanalyzable_branch_to_free_block(float %x) {
653 ; Ensure that we can handle unanalyzable branches where the destination block
654 ; gets selected as the best free block in the CFG.
656 ; CHECK: unanalyzable_branch_to_free_block
664 br i1 undef, label %a, label %b
671 %cmp = fcmp une float %x, undef
672 br i1 %cmp, label %c, label %exit
682 define void @many_unanalyzable_branches() {
683 ; Ensure that we don't crash as we're building up many unanalyzable branches,
686 ; CHECK: many_unanalyzable_branches
693 %val0 = volatile load float* undef
694 %cmp0 = fcmp une float %val0, undef
695 br i1 %cmp0, label %1, label %0
696 %val1 = volatile load float* undef
697 %cmp1 = fcmp une float %val1, undef
698 br i1 %cmp1, label %2, label %1
699 %val2 = volatile load float* undef
700 %cmp2 = fcmp une float %val2, undef
701 br i1 %cmp2, label %3, label %2
702 %val3 = volatile load float* undef
703 %cmp3 = fcmp une float %val3, undef
704 br i1 %cmp3, label %4, label %3
705 %val4 = volatile load float* undef
706 %cmp4 = fcmp une float %val4, undef
707 br i1 %cmp4, label %5, label %4
708 %val5 = volatile load float* undef
709 %cmp5 = fcmp une float %val5, undef
710 br i1 %cmp5, label %6, label %5
711 %val6 = volatile load float* undef
712 %cmp6 = fcmp une float %val6, undef
713 br i1 %cmp6, label %7, label %6
714 %val7 = volatile load float* undef
715 %cmp7 = fcmp une float %val7, undef
716 br i1 %cmp7, label %8, label %7
717 %val8 = volatile load float* undef
718 %cmp8 = fcmp une float %val8, undef
719 br i1 %cmp8, label %9, label %8
720 %val9 = volatile load float* undef
721 %cmp9 = fcmp une float %val9, undef
722 br i1 %cmp9, label %10, label %9
723 %val10 = volatile load float* undef
724 %cmp10 = fcmp une float %val10, undef
725 br i1 %cmp10, label %11, label %10
726 %val11 = volatile load float* undef
727 %cmp11 = fcmp une float %val11, undef
728 br i1 %cmp11, label %12, label %11
729 %val12 = volatile load float* undef
730 %cmp12 = fcmp une float %val12, undef
731 br i1 %cmp12, label %13, label %12
732 %val13 = volatile load float* undef
733 %cmp13 = fcmp une float %val13, undef
734 br i1 %cmp13, label %14, label %13
735 %val14 = volatile load float* undef
736 %cmp14 = fcmp une float %val14, undef
737 br i1 %cmp14, label %15, label %14
738 %val15 = volatile load float* undef
739 %cmp15 = fcmp une float %val15, undef
740 br i1 %cmp15, label %16, label %15
741 %val16 = volatile load float* undef
742 %cmp16 = fcmp une float %val16, undef
743 br i1 %cmp16, label %17, label %16
744 %val17 = volatile load float* undef
745 %cmp17 = fcmp une float %val17, undef
746 br i1 %cmp17, label %18, label %17
747 %val18 = volatile load float* undef
748 %cmp18 = fcmp une float %val18, undef
749 br i1 %cmp18, label %19, label %18
750 %val19 = volatile load float* undef
751 %cmp19 = fcmp une float %val19, undef
752 br i1 %cmp19, label %20, label %19
753 %val20 = volatile load float* undef
754 %cmp20 = fcmp une float %val20, undef
755 br i1 %cmp20, label %21, label %20
756 %val21 = volatile load float* undef
757 %cmp21 = fcmp une float %val21, undef
758 br i1 %cmp21, label %22, label %21
759 %val22 = volatile load float* undef
760 %cmp22 = fcmp une float %val22, undef
761 br i1 %cmp22, label %23, label %22
762 %val23 = volatile load float* undef
763 %cmp23 = fcmp une float %val23, undef
764 br i1 %cmp23, label %24, label %23
765 %val24 = volatile load float* undef
766 %cmp24 = fcmp une float %val24, undef
767 br i1 %cmp24, label %25, label %24
768 %val25 = volatile load float* undef
769 %cmp25 = fcmp une float %val25, undef
770 br i1 %cmp25, label %26, label %25
771 %val26 = volatile load float* undef
772 %cmp26 = fcmp une float %val26, undef
773 br i1 %cmp26, label %27, label %26
774 %val27 = volatile load float* undef
775 %cmp27 = fcmp une float %val27, undef
776 br i1 %cmp27, label %28, label %27
777 %val28 = volatile load float* undef
778 %cmp28 = fcmp une float %val28, undef
779 br i1 %cmp28, label %29, label %28
780 %val29 = volatile load float* undef
781 %cmp29 = fcmp une float %val29, undef
782 br i1 %cmp29, label %30, label %29
783 %val30 = volatile load float* undef
784 %cmp30 = fcmp une float %val30, undef
785 br i1 %cmp30, label %31, label %30
786 %val31 = volatile load float* undef
787 %cmp31 = fcmp une float %val31, undef
788 br i1 %cmp31, label %32, label %31
789 %val32 = volatile load float* undef
790 %cmp32 = fcmp une float %val32, undef
791 br i1 %cmp32, label %33, label %32
792 %val33 = volatile load float* undef
793 %cmp33 = fcmp une float %val33, undef
794 br i1 %cmp33, label %34, label %33
795 %val34 = volatile load float* undef
796 %cmp34 = fcmp une float %val34, undef
797 br i1 %cmp34, label %35, label %34
798 %val35 = volatile load float* undef
799 %cmp35 = fcmp une float %val35, undef
800 br i1 %cmp35, label %36, label %35
801 %val36 = volatile load float* undef
802 %cmp36 = fcmp une float %val36, undef
803 br i1 %cmp36, label %37, label %36
804 %val37 = volatile load float* undef
805 %cmp37 = fcmp une float %val37, undef
806 br i1 %cmp37, label %38, label %37
807 %val38 = volatile load float* undef
808 %cmp38 = fcmp une float %val38, undef
809 br i1 %cmp38, label %39, label %38
810 %val39 = volatile load float* undef
811 %cmp39 = fcmp une float %val39, undef
812 br i1 %cmp39, label %40, label %39
813 %val40 = volatile load float* undef
814 %cmp40 = fcmp une float %val40, undef
815 br i1 %cmp40, label %41, label %40
816 %val41 = volatile load float* undef
817 %cmp41 = fcmp une float %val41, undef
818 br i1 %cmp41, label %42, label %41
819 %val42 = volatile load float* undef
820 %cmp42 = fcmp une float %val42, undef
821 br i1 %cmp42, label %43, label %42
822 %val43 = volatile load float* undef
823 %cmp43 = fcmp une float %val43, undef
824 br i1 %cmp43, label %44, label %43
825 %val44 = volatile load float* undef
826 %cmp44 = fcmp une float %val44, undef
827 br i1 %cmp44, label %45, label %44
828 %val45 = volatile load float* undef
829 %cmp45 = fcmp une float %val45, undef
830 br i1 %cmp45, label %46, label %45
831 %val46 = volatile load float* undef
832 %cmp46 = fcmp une float %val46, undef
833 br i1 %cmp46, label %47, label %46
834 %val47 = volatile load float* undef
835 %cmp47 = fcmp une float %val47, undef
836 br i1 %cmp47, label %48, label %47
837 %val48 = volatile load float* undef
838 %cmp48 = fcmp une float %val48, undef
839 br i1 %cmp48, label %49, label %48
840 %val49 = volatile load float* undef
841 %cmp49 = fcmp une float %val49, undef
842 br i1 %cmp49, label %50, label %49
843 %val50 = volatile load float* undef
844 %cmp50 = fcmp une float %val50, undef
845 br i1 %cmp50, label %51, label %50
846 %val51 = volatile load float* undef
847 %cmp51 = fcmp une float %val51, undef
848 br i1 %cmp51, label %52, label %51
849 %val52 = volatile load float* undef
850 %cmp52 = fcmp une float %val52, undef
851 br i1 %cmp52, label %53, label %52
852 %val53 = volatile load float* undef
853 %cmp53 = fcmp une float %val53, undef
854 br i1 %cmp53, label %54, label %53
855 %val54 = volatile load float* undef
856 %cmp54 = fcmp une float %val54, undef
857 br i1 %cmp54, label %55, label %54
858 %val55 = volatile load float* undef
859 %cmp55 = fcmp une float %val55, undef
860 br i1 %cmp55, label %56, label %55
861 %val56 = volatile load float* undef
862 %cmp56 = fcmp une float %val56, undef
863 br i1 %cmp56, label %57, label %56
864 %val57 = volatile load float* undef
865 %cmp57 = fcmp une float %val57, undef
866 br i1 %cmp57, label %58, label %57
867 %val58 = volatile load float* undef
868 %cmp58 = fcmp une float %val58, undef
869 br i1 %cmp58, label %59, label %58
870 %val59 = volatile load float* undef
871 %cmp59 = fcmp une float %val59, undef
872 br i1 %cmp59, label %60, label %59
873 %val60 = volatile load float* undef
874 %cmp60 = fcmp une float %val60, undef
875 br i1 %cmp60, label %61, label %60
876 %val61 = volatile load float* undef
877 %cmp61 = fcmp une float %val61, undef
878 br i1 %cmp61, label %62, label %61
879 %val62 = volatile load float* undef
880 %cmp62 = fcmp une float %val62, undef
881 br i1 %cmp62, label %63, label %62
882 %val63 = volatile load float* undef
883 %cmp63 = fcmp une float %val63, undef
884 br i1 %cmp63, label %64, label %63
885 %val64 = volatile load float* undef
886 %cmp64 = fcmp une float %val64, undef
887 br i1 %cmp64, label %65, label %64