test/Transforms/LoopUnroll/runtime-loop.ll - llvm-project/llvm - Git at Google

 ; RUN: opt < %s -S -passes=loop-unroll -unroll-runtime=true -unroll-runtime-epilog=true  | FileCheck %s -check-prefixes=EPILOG,COMMON
 ; RUN: opt < %s -S -passes=loop-unroll -unroll-runtime=true -unroll-runtime-epilog=false | FileCheck %s -check-prefixes=PROLOG,COMMON
 ;
 ; RUN: opt < %s -S -passes='require<opt-remark-emit>,loop-unroll' -unroll-runtime=true -unroll-runtime-epilog=true  | FileCheck %s -check-prefixes=EPILOG,COMMON
 ; RUN: opt < %s -S -passes='require<opt-remark-emit>,loop-unroll' -unroll-runtime=true -unroll-runtime-epilog=false | FileCheck %s -check-prefixes=PROLOG,COMMON
 ;
 ; Restricted versions of unroll (unroll<peeling;noruntime>, unroll-full) should not be doing runtime unrolling
 ; even if it is globally enabled through -unroll-runtime option
 ;
 ; RUN: opt < %s -S -passes='require<opt-remark-emit>,loop-unroll<peeling;no-runtime>' -unroll-runtime=true -unroll-runtime-epilog=true  | FileCheck %s -check-prefixes=NOEPILOG,COMMON
 ; RUN: opt < %s -S -passes='require<opt-remark-emit>,loop-unroll<peeling;no-runtime>' -unroll-runtime=true -unroll-runtime-epilog=false | FileCheck %s -check-prefixes=NOPROLOG,COMMON
 ; RUN: opt < %s -S -passes='require<opt-remark-emit>,loop(loop-unroll-full)' -unroll-runtime=true -unroll-runtime-epilog=true  | FileCheck %s -check-prefixes=NOEPILOG,COMMON
 ; RUN: opt < %s -S -passes='require<opt-remark-emit>,loop(loop-unroll-full)' -unroll-runtime=true -unroll-runtime-epilog=false | FileCheck %s -check-prefixes=NOPROLOG,COMMON

 target datalayout = "e-p:64:64:64-i1:8:8-i8:8:8-i16:16:16-i32:32:32-i64:64:64-f32:32:32-f64:64:64-v64:64:64-v128:128:128-a0:0:64-s0:64:64-f80:128:128-n8:16:32:64-S128"

 ; Tests for unrolling loops with run-time trip counts

 ; COMMON-LABEL: @test(

 ; EPILOG: entry:
 ; EPILOG:   br i1 %cmp1, label %for.end, label %for.body.preheader, !prof [[EPILOG_PROF_0:![0-9]+]]
 ; EPILOG: for.body.preheader:
 ; EPILOG:   %xtraiter = and i32 %n
 ; EPILOG:   br i1 %1, label %for.end.loopexit.unr-lcssa, label %for.body.preheader.new, !prof [[EPILOG_PROF_1:![0-9]+]]

 ; EPILOG: for.end.loopexit.unr-lcssa:
 ; EPILOG:   %lcmp.mod = icmp ne i32 %xtraiter, 0
 ; EPILOG:   br i1 %lcmp.mod, label %for.body.epil.preheader, label %for.end.loopexit, !prof [[EPILOG_PROF_2:![0-9]+]]

 ; NOEPILOG-NOT: %xtraiter = and i32 %n

 ; PROLOG: entry:
 ; PROLOG:   br i1 %cmp1, label %for.end, label %for.body.preheader, !prof [[PROLOG_PROF_0:![0-9]+]]

 ; PROLOG: for.body.preheader:
 ; PROLOG:   %xtraiter = and i32 %n
 ; PROLOG:   %lcmp.mod = icmp ne i32 %xtraiter, 0
 ; PROLOG:   br i1 %lcmp.mod, label %for.body.prol.preheader, label %for.body.prol.loopexit, !prof [[PROLOG_PROF_1:![0-9]+]]

 ; NOPROLOG-NOT: %xtraiter = and i32 %n

 ; EPILOG: for.body.epil:
 ; EPILOG:   %indvars.iv.epil = phi i64 [ %indvars.iv.next.epil, %for.body.epil ],  [ %indvars.iv.unr, %for.body.epil.preheader ]
 ; EPILOG:   %epil.iter.next = add i32 %epil.iter, 1
 ; EPILOG:   %epil.iter.cmp = icmp ne i32 %epil.iter.next, %xtraiter
 ; EPILOG:   br i1 %epil.iter.cmp, label %for.body.epil, label %for.end.loopexit.epilog-lcssa, !prof [[EPILOG_PROF_3:![0-9]+]], !llvm.loop [[EPILOG_LOOP:![0-9]+]]

 ; NOEPILOG: for.body:
 ; NOEPILOG-NOT: for.body.epil:

 ; PROLOG: for.body.prol:
 ; PROLOG:   %indvars.iv.prol = phi i64 [ %indvars.iv.next.prol, %for.body.prol ], [ 0, %for.body.prol.preheader ]
 ; PROLOG:   %prol.iter.next = add i32 %prol.iter, 1
 ; PROLOG:   %prol.iter.cmp = icmp ne i32 %prol.iter.next, %xtraiter
 ; PROLOG:   br i1 %prol.iter.cmp, label %for.body.prol, label %for.body.prol.loopexit.unr-lcssa, !prof [[PROLOG_PROF_2:![0-9]+]], !llvm.loop [[PROLOG_LOOP:![0-9]+]]

 ; PROLOG: for.body.prol.loopexit:
 ; PROLOG:   br i1 %2, label %for.end.loopexit, label %for.body.preheader.new, !prof [[PROLOG_PROF_1:![0-9]+]]

 ; NOPROLOG: for.body:
 ; NOPROLOG-NOT: for.body.prol:


 define i32 @test(ptr nocapture %a, i32 %n) nounwind uwtable readonly !prof !2 {
 entry:
   %cmp1 = icmp eq i32 %n, 0
   br i1 %cmp1, label %for.end, label %for.body, !prof !3

 for.body:                                         ; preds = %for.body, %entry
   %indvars.iv = phi i64 [ %indvars.iv.next, %for.body ], [ 0, %entry ]
   %sum.02 = phi i32 [ %add, %for.body ], [ 0, %entry ]
   %arrayidx = getelementptr inbounds i32, ptr %a, i64 %indvars.iv
   %0 = load i32, ptr %arrayidx, align 4
   %add = add nsw i32 %0, %sum.02
   %indvars.iv.next = add i64 %indvars.iv, 1
   %lftr.wideiv = trunc i64 %indvars.iv.next to i32
   %exitcond = icmp eq i32 %lftr.wideiv, %n
   br i1 %exitcond, label %for.end, label %for.body, !prof !4

 for.end:                                          ; preds = %for.body, %entry
   %sum.0.lcssa = phi i32 [ 0, %entry ], [ %add, %for.body ]
   ret i32 %sum.0.lcssa
 }


 ; Still try to completely unroll loops with compile-time trip counts
 ; even if the -unroll-runtime is specified

 ; COMMON-LABEL: @test1(
 ; COMMON: for.body:
 ; COMMON-NOT: for.body.epil:
 ; COMMON-NOT: for.body.prol:

 define i32 @test1(ptr nocapture %a) nounwind uwtable readonly {
 entry:
   br label %for.body

 for.body:                                         ; preds = %for.body, %entry
   %indvars.iv = phi i64 [ 0, %entry ], [ %indvars.iv.next, %for.body ]
   %sum.01 = phi i32 [ 0, %entry ], [ %add, %for.body ]
   %arrayidx = getelementptr inbounds i32, ptr %a, i64 %indvars.iv
   %0 = load i32, ptr %arrayidx, align 4
   %add = add nsw i32 %0, %sum.01
   %indvars.iv.next = add i64 %indvars.iv, 1
   %lftr.wideiv = trunc i64 %indvars.iv.next to i32
   %exitcond = icmp eq i32 %lftr.wideiv, 5
   br i1 %exitcond, label %for.end, label %for.body

 for.end:                                          ; preds = %for.body
   ret i32 %add
 }

 ; This is test 2007-05-09-UnknownTripCount.ll which can be unrolled now
 ; if the -unroll-runtime option is turned on

 ; COMMON-LABEL: @foo(
 ; EPILOG: bb72.2:
 ; PROLOG: bb72.2:
 ; NOEPILOG-NOT: bb72.2:
 ; NOPROLOG-NOT: bb72.2:

 define void @foo(i32 %trips) {
 entry:
         br label %cond_true.outer

 cond_true.outer:
         %indvar1.ph = phi i32 [ 0, %entry ], [ %indvar.next2, %bb72 ]
         br label %bb72

 bb72:
         %indvar.next2 = add i32 %indvar1.ph, 1
         %exitcond3 = icmp eq i32 %indvar.next2, %trips
         br i1 %exitcond3, label %cond_true138, label %cond_true.outer

 cond_true138:
         ret void
 }


 ; Test run-time unrolling for a loop that counts down by -2.

 ; COMMON-LABEL: @down(
 ; EPILOG: for.body.epil:
 ; EPILOG: br i1 %epil.iter.cmp, label %for.body.epil, label %for.cond.for.end_crit_edge.epilog-lcssa

 ; NOEPILOG: for.body:
 ; NOEPILOG-NOT: for.body.epil:

 ; PROLOG: for.body.prol:
 ; PROLOG: br i1 %prol.iter.cmp, label %for.body.prol, label %for.body.prol.loopexit

 ; NOPROLOG: for.body:
 ; NOPROLOG-NOT: for.body.prol:

 define zeroext i16 @down(ptr nocapture %p, i32 %len) nounwind uwtable readonly {
 entry:
   %cmp2 = icmp eq i32 %len, 0
   br i1 %cmp2, label %for.end, label %for.body

 for.body:                                         ; preds = %for.body, %entry
   %p.addr.05 = phi ptr [ %incdec.ptr, %for.body ], [ %p, %entry ]
   %len.addr.04 = phi i32 [ %sub, %for.body ], [ %len, %entry ]
   %res.03 = phi i32 [ %add, %for.body ], [ 0, %entry ]
   %incdec.ptr = getelementptr inbounds i16, ptr %p.addr.05, i64 1
   %0 = load i16, ptr %p.addr.05, align 2
   %conv = zext i16 %0 to i32
   %add = add i32 %conv, %res.03
   %sub = add nsw i32 %len.addr.04, -2
   %cmp = icmp eq i32 %sub, 0
   br i1 %cmp, label %for.cond.for.end_crit_edge, label %for.body

 for.cond.for.end_crit_edge:                       ; preds = %for.body
   %phitmp = trunc i32 %add to i16
   br label %for.end

 for.end:                                          ; preds = %for.cond.for.end_crit_edge, %entry
   %res.0.lcssa = phi i16 [ %phitmp, %for.cond.for.end_crit_edge ], [ 0, %entry ]
   ret i16 %res.0.lcssa
 }

 ; Test run-time unrolling disable metadata.
 ; COMMON-LABEL: @test2(

 ; EPILOG: for.body:
 ; EPILOG-NOT: for.body.epil:

 ; NOEPILOG: for.body:
 ; NOEPILOG-NOT: for.body.epil:

 ; PROLOG: for.body:
 ; PROLOG-NOT: for.body.prol:

 ; NOPROLOG: for.body:
 ; NOPROLOG-NOT: for.body.prol:

 define zeroext i16 @test2(ptr nocapture %p, i32 %len) nounwind uwtable readonly {
 entry:
   %cmp2 = icmp eq i32 %len, 0
   br i1 %cmp2, label %for.end, label %for.body

 for.body:                                         ; preds = %for.body, %entry
   %p.addr.05 = phi ptr [ %incdec.ptr, %for.body ], [ %p, %entry ]
   %len.addr.04 = phi i32 [ %sub, %for.body ], [ %len, %entry ]
   %res.03 = phi i32 [ %add, %for.body ], [ 0, %entry ]
   %incdec.ptr = getelementptr inbounds i16, ptr %p.addr.05, i64 1
   %0 = load i16, ptr %p.addr.05, align 2
   %conv = zext i16 %0 to i32
   %add = add i32 %conv, %res.03
   %sub = add nsw i32 %len.addr.04, -2
   %cmp = icmp eq i32 %sub, 0
   br i1 %cmp, label %for.cond.for.end_crit_edge, label %for.body, !llvm.loop !0

 for.cond.for.end_crit_edge:                       ; preds = %for.body
   %phitmp = trunc i32 %add to i16
   br label %for.end

 for.end:                                          ; preds = %for.cond.for.end_crit_edge, %entry
   %res.0.lcssa = phi i16 [ %phitmp, %for.cond.for.end_crit_edge ], [ 0, %entry ]
   ret i16 %res.0.lcssa
 }

 ; dont unroll loop with multiple exit/exiting blocks, unless
 ; -runtime-unroll-multi-exit=true
 ; single exit, multiple exiting blocks.
 define void @unique_exit(i32 %arg) {
 ; COMMON-LABEL: @unique_exit(
 ; COMMON-NOT: .unr

 entry:
   %tmp = icmp sgt i32 undef, %arg
   br i1 %tmp, label %preheader, label %returnblock

 preheader:                                 ; preds = %entry
   br label %header

 LoopExit:                                ; preds = %header, %latch
   %tmp2.ph = phi i32 [ %tmp4, %header ], [ -1, %latch ]
   br label %returnblock

 returnblock:                                         ; preds = %LoopExit, %entry
   %tmp2 = phi i32 [ -1, %entry ], [ %tmp2.ph, %LoopExit ]
   ret void

 header:                                           ; preds = %preheader, %latch
   %tmp4 = phi i32 [ %inc, %latch ], [ %arg, %preheader ]
   %inc = add nsw i32 %tmp4, 1
   br i1 true, label %LoopExit, label %latch

 latch:                                            ; preds = %header
   %cmp = icmp slt i32 %inc, undef
   br i1 %cmp, label %header, label %LoopExit
 }

 ; multiple exit blocks. don't unroll
 define void @multi_exit(i64 %trip, i1 %cond) {
 ; COMMON-LABEL: @multi_exit(
 ; COMMON-NOT: .unr

 entry:
   br label %loop_header

 loop_header:
   %iv = phi i64 [ 0, %entry ], [ %iv_next, %loop_latch ]
   br i1 %cond, label %loop_latch, label %loop_exiting_bb1

 loop_exiting_bb1:
   br i1 false, label %loop_exiting_bb2, label %exit1

 loop_exiting_bb2:
   br i1 false, label %loop_latch, label %exit3

 exit3:
   ret void

 loop_latch:
   %iv_next = add i64 %iv, 1
   %cmp = icmp ne i64 %iv_next, %trip
   br i1 %cmp, label %loop_header, label %exit2.loopexit

 exit1:
  ret void

 exit2.loopexit:
   ret void
 }

 !0 = distinct !{!0, !1}
 !1 = !{!"llvm.loop.unroll.runtime.disable"}
 !2 = !{!"function_entry_count", i64 1}
 !3 = !{!"branch_weights", i32 1, i32 11}
 !4 = !{!"branch_weights", i32 1, i32 42}

 ; need to use LABEL here to separate function IR matching from metadata matching
 ; COMMON-LABEL: {{^}}!0 =

 ; EPILOG: [[EPILOG_PROF_0]] = !{!"branch_weights", i32 1, i32 11}
 ; EPILOG: [[EPILOG_PROF_1]] = !{!"branch_weights", i32 1, i32 127}
 ; EPILOG: [[EPILOG_PROF_2]] = !{!"branch_weights", i32 1, i32 7}
 ; EPILOG: [[EPILOG_PROF_3]] = !{!"branch_weights", i32 3, i32 1}

 ; EPILOG: [[EPILOG_LOOP]] = distinct !{[[EPILOG_LOOP]], [[EPILOG_LOOP_1:![0-9]+]]}
 ; EPILOG: [[EPILOG_LOOP_1]] = !{!"llvm.loop.unroll.disable"}

 ; PROLOG: [[PROLOG_PROF_0]] = !{!"branch_weights", i32 1, i32 11}
 ; PROLOG: [[PROLOG_PROF_1]] = !{!"branch_weights", i32 1, i32 127}
 ; PROLOG: [[PROLOG_PROF_2]] = !{!"branch_weights", i32 3, i32 1}

 ; PROLOG: distinct !{[[PROLOG_LOOP]], [[PROLOG_LOOP_1:![0-9]+]]}
 ; PROLOG: [[PROLOG_LOOP_1]] = !{!"llvm.loop.unroll.disable"}
	; RUN: opt < %s -S -passes=loop-unroll -unroll-runtime=true -unroll-runtime-epilog=true \| FileCheck %s -check-prefixes=EPILOG,COMMON
	; RUN: opt < %s -S -passes=loop-unroll -unroll-runtime=true -unroll-runtime-epilog=false \| FileCheck %s -check-prefixes=PROLOG,COMMON
	;
	; RUN: opt < %s -S -passes='require<opt-remark-emit>,loop-unroll' -unroll-runtime=true -unroll-runtime-epilog=true \| FileCheck %s -check-prefixes=EPILOG,COMMON
	; RUN: opt < %s -S -passes='require<opt-remark-emit>,loop-unroll' -unroll-runtime=true -unroll-runtime-epilog=false \| FileCheck %s -check-prefixes=PROLOG,COMMON
	;
	; Restricted versions of unroll (unroll<peeling;noruntime>, unroll-full) should not be doing runtime unrolling
	; even if it is globally enabled through -unroll-runtime option
	;
	; RUN: opt < %s -S -passes='require<opt-remark-emit>,loop-unroll<peeling;no-runtime>' -unroll-runtime=true -unroll-runtime-epilog=true \| FileCheck %s -check-prefixes=NOEPILOG,COMMON
	; RUN: opt < %s -S -passes='require<opt-remark-emit>,loop-unroll<peeling;no-runtime>' -unroll-runtime=true -unroll-runtime-epilog=false \| FileCheck %s -check-prefixes=NOPROLOG,COMMON
	; RUN: opt < %s -S -passes='require<opt-remark-emit>,loop(loop-unroll-full)' -unroll-runtime=true -unroll-runtime-epilog=true \| FileCheck %s -check-prefixes=NOEPILOG,COMMON
	; RUN: opt < %s -S -passes='require<opt-remark-emit>,loop(loop-unroll-full)' -unroll-runtime=true -unroll-runtime-epilog=false \| FileCheck %s -check-prefixes=NOPROLOG,COMMON

	target datalayout = "e-p:64:64:64-i1:8:8-i8:8:8-i16:16:16-i32:32:32-i64:64:64-f32:32:32-f64:64:64-v64:64:64-v128:128:128-a0:0:64-s0:64:64-f80:128:128-n8:16:32:64-S128"

	; Tests for unrolling loops with run-time trip counts

	; COMMON-LABEL: @test(

	; EPILOG: entry:
	; EPILOG: br i1 %cmp1, label %for.end, label %for.body.preheader, !prof [[EPILOG_PROF_0:![0-9]+]]
	; EPILOG: for.body.preheader:
	; EPILOG: %xtraiter = and i32 %n
	; EPILOG: br i1 %1, label %for.end.loopexit.unr-lcssa, label %for.body.preheader.new, !prof [[EPILOG_PROF_1:![0-9]+]]

	; EPILOG: for.end.loopexit.unr-lcssa:
	; EPILOG: %lcmp.mod = icmp ne i32 %xtraiter, 0
	; EPILOG: br i1 %lcmp.mod, label %for.body.epil.preheader, label %for.end.loopexit, !prof [[EPILOG_PROF_2:![0-9]+]]

	; NOEPILOG-NOT: %xtraiter = and i32 %n

	; PROLOG: entry:
	; PROLOG: br i1 %cmp1, label %for.end, label %for.body.preheader, !prof [[PROLOG_PROF_0:![0-9]+]]

	; PROLOG: for.body.preheader:
	; PROLOG: %xtraiter = and i32 %n
	; PROLOG: %lcmp.mod = icmp ne i32 %xtraiter, 0
	; PROLOG: br i1 %lcmp.mod, label %for.body.prol.preheader, label %for.body.prol.loopexit, !prof [[PROLOG_PROF_1:![0-9]+]]

	; NOPROLOG-NOT: %xtraiter = and i32 %n

	; EPILOG: for.body.epil:
	; EPILOG: %indvars.iv.epil = phi i64 [ %indvars.iv.next.epil, %for.body.epil ], [ %indvars.iv.unr, %for.body.epil.preheader ]
	; EPILOG: %epil.iter.next = add i32 %epil.iter, 1
	; EPILOG: %epil.iter.cmp = icmp ne i32 %epil.iter.next, %xtraiter
	; EPILOG: br i1 %epil.iter.cmp, label %for.body.epil, label %for.end.loopexit.epilog-lcssa, !prof [[EPILOG_PROF_3:![0-9]+]], !llvm.loop [[EPILOG_LOOP:![0-9]+]]

	; NOEPILOG: for.body:
	; NOEPILOG-NOT: for.body.epil:

	; PROLOG: for.body.prol:
	; PROLOG: %indvars.iv.prol = phi i64 [ %indvars.iv.next.prol, %for.body.prol ], [ 0, %for.body.prol.preheader ]
	; PROLOG: %prol.iter.next = add i32 %prol.iter, 1
	; PROLOG: %prol.iter.cmp = icmp ne i32 %prol.iter.next, %xtraiter
	; PROLOG: br i1 %prol.iter.cmp, label %for.body.prol, label %for.body.prol.loopexit.unr-lcssa, !prof [[PROLOG_PROF_2:![0-9]+]], !llvm.loop [[PROLOG_LOOP:![0-9]+]]

	; PROLOG: for.body.prol.loopexit:
	; PROLOG: br i1 %2, label %for.end.loopexit, label %for.body.preheader.new, !prof [[PROLOG_PROF_1:![0-9]+]]

	; NOPROLOG: for.body:
	; NOPROLOG-NOT: for.body.prol:


	define i32 @test(ptr nocapture %a, i32 %n) nounwind uwtable readonly !prof !2 {
	entry:
	%cmp1 = icmp eq i32 %n, 0
	br i1 %cmp1, label %for.end, label %for.body, !prof !3

	for.body: ; preds = %for.body, %entry
	%indvars.iv = phi i64 [ %indvars.iv.next, %for.body ], [ 0, %entry ]
	%sum.02 = phi i32 [ %add, %for.body ], [ 0, %entry ]
	%arrayidx = getelementptr inbounds i32, ptr %a, i64 %indvars.iv
	%0 = load i32, ptr %arrayidx, align 4
	%add = add nsw i32 %0, %sum.02
	%indvars.iv.next = add i64 %indvars.iv, 1
	%lftr.wideiv = trunc i64 %indvars.iv.next to i32
	%exitcond = icmp eq i32 %lftr.wideiv, %n
	br i1 %exitcond, label %for.end, label %for.body, !prof !4

	for.end: ; preds = %for.body, %entry
	%sum.0.lcssa = phi i32 [ 0, %entry ], [ %add, %for.body ]
	ret i32 %sum.0.lcssa
	}


	; Still try to completely unroll loops with compile-time trip counts
	; even if the -unroll-runtime is specified

	; COMMON-LABEL: @test1(
	; COMMON: for.body:
	; COMMON-NOT: for.body.epil:
	; COMMON-NOT: for.body.prol:

	define i32 @test1(ptr nocapture %a) nounwind uwtable readonly {
	entry:
	br label %for.body

	for.body: ; preds = %for.body, %entry
	%indvars.iv = phi i64 [ 0, %entry ], [ %indvars.iv.next, %for.body ]
	%sum.01 = phi i32 [ 0, %entry ], [ %add, %for.body ]
	%arrayidx = getelementptr inbounds i32, ptr %a, i64 %indvars.iv
	%0 = load i32, ptr %arrayidx, align 4
	%add = add nsw i32 %0, %sum.01
	%indvars.iv.next = add i64 %indvars.iv, 1
	%lftr.wideiv = trunc i64 %indvars.iv.next to i32
	%exitcond = icmp eq i32 %lftr.wideiv, 5
	br i1 %exitcond, label %for.end, label %for.body

	for.end: ; preds = %for.body
	ret i32 %add
	}

	; This is test 2007-05-09-UnknownTripCount.ll which can be unrolled now
	; if the -unroll-runtime option is turned on

	; COMMON-LABEL: @foo(
	; EPILOG: bb72.2:
	; PROLOG: bb72.2:
	; NOEPILOG-NOT: bb72.2:
	; NOPROLOG-NOT: bb72.2:

	define void @foo(i32 %trips) {
	entry:
	br label %cond_true.outer

	cond_true.outer:
	%indvar1.ph = phi i32 [ 0, %entry ], [ %indvar.next2, %bb72 ]
	br label %bb72

	bb72:
	%indvar.next2 = add i32 %indvar1.ph, 1
	%exitcond3 = icmp eq i32 %indvar.next2, %trips
	br i1 %exitcond3, label %cond_true138, label %cond_true.outer

	cond_true138:
	ret void
	}


	; Test run-time unrolling for a loop that counts down by -2.

	; COMMON-LABEL: @down(
	; EPILOG: for.body.epil:
	; EPILOG: br i1 %epil.iter.cmp, label %for.body.epil, label %for.cond.for.end_crit_edge.epilog-lcssa

	; NOEPILOG: for.body:
	; NOEPILOG-NOT: for.body.epil:

	; PROLOG: for.body.prol:
	; PROLOG: br i1 %prol.iter.cmp, label %for.body.prol, label %for.body.prol.loopexit

	; NOPROLOG: for.body:
	; NOPROLOG-NOT: for.body.prol:

	define zeroext i16 @down(ptr nocapture %p, i32 %len) nounwind uwtable readonly {
	entry:
	%cmp2 = icmp eq i32 %len, 0
	br i1 %cmp2, label %for.end, label %for.body

	for.body: ; preds = %for.body, %entry
	%p.addr.05 = phi ptr [ %incdec.ptr, %for.body ], [ %p, %entry ]
	%len.addr.04 = phi i32 [ %sub, %for.body ], [ %len, %entry ]
	%res.03 = phi i32 [ %add, %for.body ], [ 0, %entry ]
	%incdec.ptr = getelementptr inbounds i16, ptr %p.addr.05, i64 1
	%0 = load i16, ptr %p.addr.05, align 2
	%conv = zext i16 %0 to i32
	%add = add i32 %conv, %res.03
	%sub = add nsw i32 %len.addr.04, -2
	%cmp = icmp eq i32 %sub, 0
	br i1 %cmp, label %for.cond.for.end_crit_edge, label %for.body

	for.cond.for.end_crit_edge: ; preds = %for.body
	%phitmp = trunc i32 %add to i16
	br label %for.end

	for.end: ; preds = %for.cond.for.end_crit_edge, %entry
	%res.0.lcssa = phi i16 [ %phitmp, %for.cond.for.end_crit_edge ], [ 0, %entry ]
	ret i16 %res.0.lcssa
	}

	; Test run-time unrolling disable metadata.
	; COMMON-LABEL: @test2(

	; EPILOG: for.body:
	; EPILOG-NOT: for.body.epil:

	; NOEPILOG: for.body:
	; NOEPILOG-NOT: for.body.epil:

	; PROLOG: for.body:
	; PROLOG-NOT: for.body.prol:

	; NOPROLOG: for.body:
	; NOPROLOG-NOT: for.body.prol:

	define zeroext i16 @test2(ptr nocapture %p, i32 %len) nounwind uwtable readonly {
	entry:
	%cmp2 = icmp eq i32 %len, 0
	br i1 %cmp2, label %for.end, label %for.body

	for.body: ; preds = %for.body, %entry
	%p.addr.05 = phi ptr [ %incdec.ptr, %for.body ], [ %p, %entry ]
	%len.addr.04 = phi i32 [ %sub, %for.body ], [ %len, %entry ]
	%res.03 = phi i32 [ %add, %for.body ], [ 0, %entry ]
	%incdec.ptr = getelementptr inbounds i16, ptr %p.addr.05, i64 1
	%0 = load i16, ptr %p.addr.05, align 2
	%conv = zext i16 %0 to i32
	%add = add i32 %conv, %res.03
	%sub = add nsw i32 %len.addr.04, -2
	%cmp = icmp eq i32 %sub, 0
	br i1 %cmp, label %for.cond.for.end_crit_edge, label %for.body, !llvm.loop !0

	for.cond.for.end_crit_edge: ; preds = %for.body
	%phitmp = trunc i32 %add to i16
	br label %for.end

	for.end: ; preds = %for.cond.for.end_crit_edge, %entry
	%res.0.lcssa = phi i16 [ %phitmp, %for.cond.for.end_crit_edge ], [ 0, %entry ]
	ret i16 %res.0.lcssa
	}

	; dont unroll loop with multiple exit/exiting blocks, unless
	; -runtime-unroll-multi-exit=true
	; single exit, multiple exiting blocks.
	define void @unique_exit(i32 %arg) {
	; COMMON-LABEL: @unique_exit(
	; COMMON-NOT: .unr

	entry:
	%tmp = icmp sgt i32 undef, %arg
	br i1 %tmp, label %preheader, label %returnblock

	preheader: ; preds = %entry
	br label %header

	LoopExit: ; preds = %header, %latch
	%tmp2.ph = phi i32 [ %tmp4, %header ], [ -1, %latch ]
	br label %returnblock

	returnblock: ; preds = %LoopExit, %entry
	%tmp2 = phi i32 [ -1, %entry ], [ %tmp2.ph, %LoopExit ]
	ret void

	header: ; preds = %preheader, %latch
	%tmp4 = phi i32 [ %inc, %latch ], [ %arg, %preheader ]
	%inc = add nsw i32 %tmp4, 1
	br i1 true, label %LoopExit, label %latch

	latch: ; preds = %header
	%cmp = icmp slt i32 %inc, undef
	br i1 %cmp, label %header, label %LoopExit
	}

	; multiple exit blocks. don't unroll
	define void @multi_exit(i64 %trip, i1 %cond) {
	; COMMON-LABEL: @multi_exit(
	; COMMON-NOT: .unr

	entry:
	br label %loop_header

	loop_header:
	%iv = phi i64 [ 0, %entry ], [ %iv_next, %loop_latch ]
	br i1 %cond, label %loop_latch, label %loop_exiting_bb1

	loop_exiting_bb1:
	br i1 false, label %loop_exiting_bb2, label %exit1

	loop_exiting_bb2:
	br i1 false, label %loop_latch, label %exit3

	exit3:
	ret void

	loop_latch:
	%iv_next = add i64 %iv, 1
	%cmp = icmp ne i64 %iv_next, %trip
	br i1 %cmp, label %loop_header, label %exit2.loopexit

	exit1:
	ret void

	exit2.loopexit:
	ret void
	}

	!0 = distinct !{!0, !1}
	!1 = !{!"llvm.loop.unroll.runtime.disable"}
	!2 = !{!"function_entry_count", i64 1}
	!3 = !{!"branch_weights", i32 1, i32 11}
	!4 = !{!"branch_weights", i32 1, i32 42}

	; need to use LABEL here to separate function IR matching from metadata matching
	; COMMON-LABEL: {{^}}!0 =

	; EPILOG: [[EPILOG_PROF_0]] = !{!"branch_weights", i32 1, i32 11}
	; EPILOG: [[EPILOG_PROF_1]] = !{!"branch_weights", i32 1, i32 127}
	; EPILOG: [[EPILOG_PROF_2]] = !{!"branch_weights", i32 1, i32 7}
	; EPILOG: [[EPILOG_PROF_3]] = !{!"branch_weights", i32 3, i32 1}

	; EPILOG: [[EPILOG_LOOP]] = distinct !{[[EPILOG_LOOP]], [[EPILOG_LOOP_1:![0-9]+]]}
	; EPILOG: [[EPILOG_LOOP_1]] = !{!"llvm.loop.unroll.disable"}

	; PROLOG: [[PROLOG_PROF_0]] = !{!"branch_weights", i32 1, i32 11}
	; PROLOG: [[PROLOG_PROF_1]] = !{!"branch_weights", i32 1, i32 127}
	; PROLOG: [[PROLOG_PROF_2]] = !{!"branch_weights", i32 3, i32 1}

	; PROLOG: distinct !{[[PROLOG_LOOP]], [[PROLOG_LOOP_1:![0-9]+]]}
	; PROLOG: [[PROLOG_LOOP_1]] = !{!"llvm.loop.unroll.disable"}