|  | ; RUN: opt -indvars -S < %s | FileCheck %s | 
|  |  | 
|  | 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" | 
|  |  | 
|  | @X = external global [0 x double] | 
|  |  | 
|  | ; Indvars should be able to simplify simple comparisons involving | 
|  | ; induction variables. | 
|  |  | 
|  | ; CHECK-LABEL: @foo( | 
|  | ; CHECK: %cond = and i1 %tobool.not, true | 
|  |  | 
|  | define void @foo(i64 %n, i32* nocapture %p) nounwind { | 
|  | entry: | 
|  | %cmp9 = icmp sgt i64 %n, 0 | 
|  | br i1 %cmp9, label %pre, label %return | 
|  |  | 
|  | pre: | 
|  | %t3 = load i32, i32* %p | 
|  | %tobool.not = icmp ne i32 %t3, 0 | 
|  | br label %loop | 
|  |  | 
|  | loop: | 
|  | %i = phi i64 [ 0, %pre ], [ %inc, %for.inc ] | 
|  | %cmp6 = icmp slt i64 %i, %n | 
|  | %cond = and i1 %tobool.not, %cmp6 | 
|  | br i1 %cond, label %if.then, label %for.inc | 
|  |  | 
|  | if.then: | 
|  | %arrayidx = getelementptr [0 x double], [0 x double]* @X, i64 0, i64 %i | 
|  | store double 3.200000e+00, double* %arrayidx | 
|  | br label %for.inc | 
|  |  | 
|  | for.inc: | 
|  | %inc = add nsw i64 %i, 1 | 
|  | %exitcond = icmp sge i64 %inc, %n | 
|  | br i1 %exitcond, label %return, label %loop | 
|  |  | 
|  | return: | 
|  | ret void | 
|  | } | 
|  |  | 
|  | ; Don't eliminate an icmp that's contributing to the loop exit test though. | 
|  |  | 
|  | ; CHECK-LABEL: @_ZNK4llvm5APInt3ultERKS0_( | 
|  | ; CHECK: %tmp99 = icmp sgt i32 %i, -1 | 
|  |  | 
|  | define i32 @_ZNK4llvm5APInt3ultERKS0_(i32 %tmp2.i1, i64** %tmp65, i64** %tmp73, i64** %tmp82, i64** %tmp90) { | 
|  | entry: | 
|  | br label %bb18 | 
|  |  | 
|  | bb13: | 
|  | %tmp66 = load i64*, i64** %tmp65, align 4 | 
|  | %tmp68 = getelementptr inbounds i64, i64* %tmp66, i32 %i | 
|  | %tmp69 = load i64, i64* %tmp68, align 4 | 
|  | %tmp74 = load i64*, i64** %tmp73, align 4 | 
|  | %tmp76 = getelementptr inbounds i64, i64* %tmp74, i32 %i | 
|  | %tmp77 = load i64, i64* %tmp76, align 4 | 
|  | %tmp78 = icmp ugt i64 %tmp69, %tmp77 | 
|  | br i1 %tmp78, label %bb20.loopexit, label %bb15 | 
|  |  | 
|  | bb15: | 
|  | %tmp83 = load i64*, i64** %tmp82, align 4 | 
|  | %tmp85 = getelementptr inbounds i64, i64* %tmp83, i32 %i | 
|  | %tmp86 = load i64, i64* %tmp85, align 4 | 
|  | %tmp91 = load i64*, i64** %tmp90, align 4 | 
|  | %tmp93 = getelementptr inbounds i64, i64* %tmp91, i32 %i | 
|  | %tmp94 = load i64, i64* %tmp93, align 4 | 
|  | %tmp95 = icmp ult i64 %tmp86, %tmp94 | 
|  | br i1 %tmp95, label %bb20.loopexit, label %bb17 | 
|  |  | 
|  | bb17: | 
|  | %tmp97 = add nsw i32 %i, -1 | 
|  | br label %bb18 | 
|  |  | 
|  | bb18: | 
|  | %i = phi i32 [ %tmp2.i1, %entry ], [ %tmp97, %bb17 ] | 
|  | %tmp99 = icmp sgt i32 %i, -1 | 
|  | br i1 %tmp99, label %bb13, label %bb20.loopexit | 
|  |  | 
|  | bb20.loopexit: | 
|  | %tmp.0.ph = phi i32 [ 0, %bb18 ], [ 1, %bb15 ], [ 0, %bb13 ] | 
|  | ret i32 %tmp.0.ph | 
|  | } | 
|  |  | 
|  | ; Indvars should eliminate the icmp here. | 
|  |  | 
|  | ; CHECK-LABEL: @func_10( | 
|  | ; CHECK-NOT: icmp | 
|  | ; CHECK: ret void | 
|  |  | 
|  | define void @func_10() nounwind { | 
|  | entry: | 
|  | br label %loop | 
|  |  | 
|  | loop: | 
|  | %i = phi i32 [ %i.next, %loop ], [ 0, %entry ] | 
|  | %t0 = icmp slt i32 %i, 0 | 
|  | %t1 = zext i1 %t0 to i32 | 
|  | %t2 = add i32 %t1, %i | 
|  | %u3 = zext i32 %t2 to i64 | 
|  | store i64 %u3, i64* null | 
|  | %i.next = add i32 %i, 1 | 
|  | br i1 undef, label %loop, label %return | 
|  |  | 
|  | return: | 
|  | ret void | 
|  | } | 
|  |  | 
|  | ; PR14432 | 
|  | ; Indvars should not turn the second loop into an infinite one. | 
|  |  | 
|  | ; CHECK-LABEL: @func_11( | 
|  | ; CHECK: %tmp5 = icmp ult i32 %__key6.0, 10 | 
|  | ; CHECK-NOT: br i1 true, label %noassert68, label %unrolledend | 
|  |  | 
|  | define i32 @func_11() nounwind uwtable { | 
|  | entry: | 
|  | br label %forcond | 
|  |  | 
|  | forcond:                                          ; preds = %noassert, %entry | 
|  | %__key6.0 = phi i32 [ 2, %entry ], [ %tmp37, %noassert ] | 
|  | %tmp5 = icmp slt i32 %__key6.0, 10 | 
|  | br i1 %tmp5, label %noassert, label %forcond38.preheader | 
|  |  | 
|  | forcond38.preheader:                              ; preds = %forcond | 
|  | br label %forcond38 | 
|  |  | 
|  | noassert:                                         ; preds = %forbody | 
|  | %tmp13 = sdiv i32 -32768, %__key6.0 | 
|  | %tmp2936 = shl i32 %tmp13, 24 | 
|  | %sext23 = shl i32 %tmp13, 24 | 
|  | %tmp32 = icmp eq i32 %tmp2936, %sext23 | 
|  | %tmp37 = add i32 %__key6.0, 1 | 
|  | br i1 %tmp32, label %forcond, label %assert33 | 
|  |  | 
|  | assert33:                                         ; preds = %noassert | 
|  | tail call void @llvm.trap() | 
|  | unreachable | 
|  |  | 
|  | forcond38:                                        ; preds = %noassert68, %forcond38.preheader | 
|  | %__key8.0 = phi i32 [ %tmp81, %noassert68 ], [ 2, %forcond38.preheader ] | 
|  | %tmp46 = icmp slt i32 %__key8.0, 10 | 
|  | br i1 %tmp46, label %noassert68, label %unrolledend | 
|  |  | 
|  | noassert68:                                       ; preds = %forbody39 | 
|  | %tmp57 = sdiv i32 -32768, %__key8.0 | 
|  | %sext34 = shl i32 %tmp57, 16 | 
|  | %sext21 = shl i32 %tmp57, 16 | 
|  | %tmp76 = icmp eq i32 %sext34, %sext21 | 
|  | %tmp81 = add i32 %__key8.0, 1 | 
|  | br i1 %tmp76, label %forcond38, label %assert77 | 
|  |  | 
|  | assert77:                                         ; preds = %noassert68 | 
|  | tail call void @llvm.trap() | 
|  | unreachable | 
|  |  | 
|  | unrolledend:                                      ; preds = %forcond38 | 
|  | ret i32 0 | 
|  | } | 
|  |  | 
|  | declare void @llvm.trap() noreturn nounwind | 
|  |  | 
|  | ; In this case the second loop only has a single iteration, fold the header away | 
|  | ; CHECK-LABEL: @func_12( | 
|  | ; CHECK: %tmp5 = icmp ult i32 %__key6.0, 10 | 
|  | ; CHECK: br i1 true, label %noassert68, label %unrolledend | 
|  | define i32 @func_12() nounwind uwtable { | 
|  | entry: | 
|  | br label %forcond | 
|  |  | 
|  | forcond:                                          ; preds = %noassert, %entry | 
|  | %__key6.0 = phi i32 [ 2, %entry ], [ %tmp37, %noassert ] | 
|  | %tmp5 = icmp slt i32 %__key6.0, 10 | 
|  | br i1 %tmp5, label %noassert, label %forcond38.preheader | 
|  |  | 
|  | forcond38.preheader:                              ; preds = %forcond | 
|  | br label %forcond38 | 
|  |  | 
|  | noassert:                                         ; preds = %forbody | 
|  | %tmp13 = sdiv i32 -32768, %__key6.0 | 
|  | %tmp2936 = shl i32 %tmp13, 24 | 
|  | %sext23 = shl i32 %tmp13, 24 | 
|  | %tmp32 = icmp eq i32 %tmp2936, %sext23 | 
|  | %tmp37 = add i32 %__key6.0, 1 | 
|  | br i1 %tmp32, label %forcond, label %assert33 | 
|  |  | 
|  | assert33:                                         ; preds = %noassert | 
|  | tail call void @llvm.trap() | 
|  | unreachable | 
|  |  | 
|  | forcond38:                                        ; preds = %noassert68, %forcond38.preheader | 
|  | %__key8.0 = phi i32 [ %tmp81, %noassert68 ], [ 2, %forcond38.preheader ] | 
|  | %tmp46 = icmp slt i32 %__key8.0, 10 | 
|  | br i1 %tmp46, label %noassert68, label %unrolledend | 
|  |  | 
|  | noassert68:                                       ; preds = %forbody39 | 
|  | %tmp57 = sdiv i32 -32768, %__key8.0 | 
|  | %sext34 = shl i32 %tmp57, 16 | 
|  | %sext21 = shl i32 %tmp57, 16 | 
|  | %tmp76 = icmp ne i32 %sext34, %sext21 | 
|  | %tmp81 = add i32 %__key8.0, 1 | 
|  | br i1 %tmp76, label %forcond38, label %assert77 | 
|  |  | 
|  | assert77:                                         ; preds = %noassert68 | 
|  | tail call void @llvm.trap() | 
|  | unreachable | 
|  |  | 
|  | unrolledend:                                      ; preds = %forcond38 | 
|  | ret i32 0 | 
|  | } | 
|  |  | 
|  | declare void @side_effect() | 
|  |  | 
|  | define void @func_13(i32* %len.ptr) { | 
|  | ; CHECK-LABEL: @func_13( | 
|  | entry: | 
|  | %len = load i32, i32* %len.ptr, !range !0 | 
|  | %len.sub.1 = add i32 %len, -1 | 
|  | %len.is.zero = icmp eq i32 %len, 0 | 
|  | br i1 %len.is.zero, label %leave, label %loop | 
|  |  | 
|  | loop: | 
|  | ; CHECK: loop: | 
|  | %iv = phi i32 [ 0, %entry ], [ %iv.inc, %be ] | 
|  | call void @side_effect() | 
|  | %iv.inc = add i32 %iv, 1 | 
|  | %iv.cmp = icmp ult i32 %iv, %len | 
|  | br i1 %iv.cmp, label %be, label %leave | 
|  | ; CHECK: br i1 true, label %be, label %leave | 
|  |  | 
|  | be: | 
|  | call void @side_effect() | 
|  | %be.cond = icmp ult i32 %iv, %len.sub.1 | 
|  | br i1 %be.cond, label %loop, label %leave | 
|  |  | 
|  | leave: | 
|  | ret void | 
|  | } | 
|  |  | 
|  | define void @func_14(i32* %len.ptr) { | 
|  | ; CHECK-LABEL: @func_14( | 
|  | entry: | 
|  | %len = load i32, i32* %len.ptr, !range !0 | 
|  | %len.sub.1 = add i32 %len, -1 | 
|  | %len.is.zero = icmp eq i32 %len, 0 | 
|  | %len.is.int_min = icmp eq i32 %len, 2147483648 | 
|  | %no.entry = or i1 %len.is.zero, %len.is.int_min | 
|  | br i1 %no.entry, label %leave, label %loop | 
|  |  | 
|  | loop: | 
|  | ; CHECK: loop: | 
|  | %iv = phi i32 [ 0, %entry ], [ %iv.inc, %be ] | 
|  | call void @side_effect() | 
|  | %iv.inc = add i32 %iv, 1 | 
|  | %iv.cmp = icmp slt i32 %iv, %len | 
|  | br i1 %iv.cmp, label %be, label %leave | 
|  | ; CHECK: br i1 true, label %be, label %leave | 
|  |  | 
|  | be: | 
|  | call void @side_effect() | 
|  | %be.cond = icmp slt i32 %iv, %len.sub.1 | 
|  | br i1 %be.cond, label %loop, label %leave | 
|  |  | 
|  | leave: | 
|  | ret void | 
|  | } | 
|  |  | 
|  | define void @func_15(i32* %len.ptr) { | 
|  | ; CHECK-LABEL: @func_15( | 
|  | entry: | 
|  | %len = load i32, i32* %len.ptr, !range !0 | 
|  | %len.add.1 = add i32 %len, 1 | 
|  | %len.add.1.is.zero = icmp eq i32 %len.add.1, 0 | 
|  | br i1 %len.add.1.is.zero, label %leave, label %loop | 
|  |  | 
|  | loop: | 
|  | ; CHECK: loop: | 
|  | %iv = phi i32 [ 0, %entry ], [ %iv.inc, %be ] | 
|  | call void @side_effect() | 
|  | %iv.inc = add i32 %iv, 1 | 
|  | %iv.cmp = icmp ult i32 %iv, %len.add.1 | 
|  | br i1 %iv.cmp, label %be, label %leave | 
|  | ; CHECK: br i1 true, label %be, label %leave | 
|  |  | 
|  | be: | 
|  | call void @side_effect() | 
|  | %be.cond = icmp ult i32 %iv, %len | 
|  | br i1 %be.cond, label %loop, label %leave | 
|  |  | 
|  | leave: | 
|  | ret void | 
|  | } | 
|  |  | 
|  | define void @func_16(i32* %len.ptr) { | 
|  | ; CHECK-LABEL: @func_16( | 
|  | entry: | 
|  | %len = load i32, i32* %len.ptr, !range !0 | 
|  | %len.add.5 = add i32 %len, 5 | 
|  | %entry.cond.0 = icmp slt i32 %len, 2147483643 | 
|  | %entry.cond.1 = icmp slt i32 4, %len.add.5 | 
|  | %entry.cond = and i1 %entry.cond.0, %entry.cond.1 | 
|  | br i1 %entry.cond, label %loop, label %leave | 
|  |  | 
|  | loop: | 
|  | ; CHECK: loop: | 
|  | %iv = phi i32 [ 0, %entry ], [ %iv.inc, %be ] | 
|  | call void @side_effect() | 
|  | %iv.inc = add i32 %iv, 1 | 
|  | %iv.add.4 = add i32 %iv, 4 | 
|  | %iv.cmp = icmp slt i32 %iv.add.4, %len.add.5 | 
|  | br i1 %iv.cmp, label %be, label %leave | 
|  | ; CHECK: br i1 true, label %be, label %leave | 
|  |  | 
|  | be: | 
|  | call void @side_effect() | 
|  | %be.cond = icmp slt i32 %iv, %len | 
|  | br i1 %be.cond, label %loop, label %leave | 
|  |  | 
|  | leave: | 
|  | ret void | 
|  | } | 
|  |  | 
|  | define void @func_17(i32* %len.ptr) { | 
|  | ; CHECK-LABEL: @func_17( | 
|  | entry: | 
|  | %len = load i32, i32* %len.ptr | 
|  | %len.add.5 = add i32 %len, -5 | 
|  | %entry.cond.0 = icmp slt i32 %len, 2147483653 ;; 2147483653 == INT_MIN - (-5) | 
|  | %entry.cond.1 = icmp slt i32 -6, %len.add.5 | 
|  | %entry.cond = and i1 %entry.cond.0, %entry.cond.1 | 
|  | br i1 %entry.cond, label %loop, label %leave | 
|  |  | 
|  | loop: | 
|  | ; CHECK: loop: | 
|  | %iv.2 = phi i32 [ 0, %entry ], [ %iv.2.inc, %be ] | 
|  | %iv = phi i32 [ -6, %entry ], [ %iv.inc, %be ] | 
|  | call void @side_effect() | 
|  | %iv.inc = add i32 %iv, 1 | 
|  | %iv.2.inc = add i32 %iv.2, 1 | 
|  | %iv.cmp = icmp slt i32 %iv, %len.add.5 | 
|  |  | 
|  | ; Deduces {-5,+,1} s< (-5 + %len) from {0,+,1} < %len | 
|  | ; since %len s< INT_MIN - (-5) from the entry condition | 
|  |  | 
|  | ; CHECK: br i1 true, label %be, label %leave | 
|  | br i1 %iv.cmp, label %be, label %leave | 
|  |  | 
|  | be: | 
|  | ; CHECK: be: | 
|  | call void @side_effect() | 
|  | %be.cond = icmp slt i32 %iv.2, %len | 
|  | br i1 %be.cond, label %loop, label %leave | 
|  |  | 
|  | leave: | 
|  | ret void | 
|  | } | 
|  |  | 
|  | define i1 @func_18(i16* %tmp20, i32* %len.addr) { | 
|  | ; CHECK-LABEL: @func_18( | 
|  | entry: | 
|  | %len = load i32, i32* %len.addr, !range !0 | 
|  | %tmp18 = icmp eq i32 %len, 0 | 
|  | br i1 %tmp18, label %bb2, label %bb0.preheader | 
|  |  | 
|  | bb0.preheader: | 
|  | br label %bb0 | 
|  |  | 
|  | bb0: | 
|  | ; CHECK: bb0: | 
|  | %var_0.in = phi i32 [ %var_0, %bb1 ], [ %len, %bb0.preheader ] | 
|  | %var_1 = phi i32 [ %tmp30, %bb1 ], [ 0, %bb0.preheader ] | 
|  | %var_0 = add nsw i32 %var_0.in, -1 | 
|  | %tmp23 = icmp ult i32 %var_1, %len | 
|  | ; CHECK: br i1 true, label %stay, label %bb2.loopexit | 
|  | br i1 %tmp23, label %stay, label %bb2 | 
|  |  | 
|  | stay: | 
|  | ; CHECK: stay: | 
|  | %tmp25 = getelementptr inbounds i16, i16* %tmp20, i32 %var_1 | 
|  | %tmp26 = load i16, i16* %tmp25 | 
|  | %tmp29 = icmp eq i16 %tmp26, 0 | 
|  | br i1 %tmp29, label %bb1, label %bb2 | 
|  |  | 
|  | bb1: | 
|  | %tmp30 = add i32 %var_1, 1 | 
|  | %tmp31 = icmp eq i32 %var_0, 0 | 
|  | br i1 %tmp31, label %bb3, label %bb0 | 
|  |  | 
|  | bb2: | 
|  | ret i1 false | 
|  |  | 
|  | bb3: | 
|  | ret i1 true | 
|  | } | 
|  |  | 
|  | define void @func_19(i32* %length.ptr) { | 
|  | ; CHECK-LABEL: @func_19( | 
|  | entry: | 
|  | %length = load i32, i32* %length.ptr, !range !0 | 
|  | %length.is.nonzero = icmp ne i32 %length, 0 | 
|  | br i1 %length.is.nonzero, label %loop, label %leave | 
|  |  | 
|  | loop: | 
|  | ; CHECK: loop: | 
|  | %iv = phi i32 [ 0, %entry ], [ %iv.inc, %be ] | 
|  | %iv.inc = add i32 %iv, 1 | 
|  | %range.check = icmp ult i32 %iv, %length | 
|  | br i1 %range.check, label %be, label %leave | 
|  | ; CHECK:   br i1 true, label %be, label %leave.loopexit | 
|  | ; CHECK: be: | 
|  |  | 
|  | be: | 
|  | call void @side_effect() | 
|  | %be.cond = icmp slt i32 %iv.inc, %length | 
|  | br i1 %be.cond, label %loop, label %leave | 
|  |  | 
|  | leave: | 
|  | ret void | 
|  | } | 
|  |  | 
|  | define void @func_20(i32* %length.ptr) { | 
|  | ; Like @func_19, but %length is no longer provably positive, so | 
|  | ; %range.check cannot be proved to be always true. | 
|  |  | 
|  | ; CHECK-LABEL: @func_20( | 
|  | entry: | 
|  | %length = load i32, i32* %length.ptr | 
|  | %length.is.nonzero = icmp ne i32 %length, 0 | 
|  | br i1 %length.is.nonzero, label %loop, label %leave | 
|  |  | 
|  | loop: | 
|  | ; CHECK: loop: | 
|  | %iv = phi i32 [ 0, %entry ], [ %iv.inc, %be ] | 
|  | %iv.inc = add i32 %iv, 1 | 
|  | %range.check = icmp ult i32 %iv, %length | 
|  | br i1 %range.check, label %be, label %leave | 
|  | ; CHECK:   br i1 %range.check, label %be, label %leave.loopexit | 
|  | ; CHECK: be: | 
|  |  | 
|  | be: | 
|  | call void @side_effect() | 
|  | %be.cond = icmp slt i32 %iv.inc, %length | 
|  | br i1 %be.cond, label %loop, label %leave | 
|  |  | 
|  | leave: | 
|  | ret void | 
|  | } | 
|  |  | 
|  | define void @func_21(i32* %length.ptr) { | 
|  | ; CHECK-LABEL: @func_21( | 
|  |  | 
|  | ; This checks that the backedge condition, (I + 1) < Length - 1 implies | 
|  | ; (I + 1) < Length | 
|  | entry: | 
|  | %length = load i32, i32* %length.ptr, !range !0 | 
|  | %lim = sub i32 %length, 1 | 
|  | %entry.cond = icmp sgt i32 %length, 1 | 
|  | br i1 %entry.cond, label %loop, label %leave | 
|  |  | 
|  | loop: | 
|  | ; CHECK: loop: | 
|  | %iv = phi i32 [ 0, %entry ], [ %iv.inc, %be ] | 
|  | %iv.inc = add i32 %iv, 1 | 
|  | %range.check = icmp slt i32 %iv, %length | 
|  | br i1 %range.check, label %be, label %leave | 
|  | ; CHECK:   br i1 true, label %be, label %leave.loopexit | 
|  | ; CHECK: be: | 
|  |  | 
|  | be: | 
|  | call void @side_effect() | 
|  | %be.cond = icmp slt i32 %iv.inc, %lim | 
|  | br i1 %be.cond, label %loop, label %leave | 
|  |  | 
|  | leave: | 
|  | ret void | 
|  | } | 
|  |  | 
|  | define void @func_22(i32* %length.ptr) { | 
|  | ; CHECK-LABEL: @func_22( | 
|  |  | 
|  | ; This checks that the backedge condition, (I + 1) < Length - 1 implies | 
|  | ; (I + 1) < Length | 
|  | entry: | 
|  | %length = load i32, i32* %length.ptr, !range !0 | 
|  | %lim = sub i32 %length, 1 | 
|  | %entry.cond = icmp sgt i32 %length, 1 | 
|  | br i1 %entry.cond, label %loop, label %leave | 
|  |  | 
|  | loop: | 
|  | ; CHECK: loop: | 
|  | %iv = phi i32 [ 0, %entry ], [ %iv.inc, %be ] | 
|  | %iv.inc = add i32 %iv, 1 | 
|  | %range.check = icmp sle i32 %iv, %length | 
|  | br i1 %range.check, label %be, label %leave | 
|  | ; CHECK:   br i1 true, label %be, label %leave.loopexit | 
|  | ; CHECK: be: | 
|  |  | 
|  | be: | 
|  | call void @side_effect() | 
|  | %be.cond = icmp sle i32 %iv.inc, %lim | 
|  | br i1 %be.cond, label %loop, label %leave | 
|  |  | 
|  | leave: | 
|  | ret void | 
|  | } | 
|  |  | 
|  | define void @func_23(i32* %length.ptr) { | 
|  | ; CHECK-LABEL: @func_23( | 
|  | entry: | 
|  | %length = load i32, i32* %length.ptr, !range !0 | 
|  | %entry.cond = icmp ult i32 4, %length | 
|  | br i1 %entry.cond, label %loop, label %leave | 
|  |  | 
|  | loop: | 
|  | ; CHECK: loop: | 
|  | %iv = phi i32 [ 4, %entry ], [ %iv.inc, %be ] | 
|  | %iv.inc = add i32 %iv, 1 | 
|  | %range.check = icmp slt i32 %iv, %length | 
|  | br i1 %range.check, label %be, label %leave | 
|  | ; CHECK:   br i1 true, label %be, label %leave.loopexit | 
|  | ; CHECK: be: | 
|  |  | 
|  | be: | 
|  | call void @side_effect() | 
|  | %be.cond = icmp slt i32 %iv.inc, %length | 
|  | br i1 %be.cond, label %loop, label %leave | 
|  |  | 
|  | leave: | 
|  | ret void | 
|  | } | 
|  |  | 
|  | define void @func_24(i32* %init.ptr) { | 
|  | ; CHECK-LABEL: @func_24( | 
|  | entry: | 
|  | %init = load i32, i32* %init.ptr, !range !0 | 
|  | %entry.cond = icmp ugt i32 %init, 4 | 
|  | br i1 %entry.cond, label %loop, label %leave | 
|  |  | 
|  | loop: | 
|  | ; CHECK: loop: | 
|  | %iv = phi i32 [ %init, %entry ], [ %iv.dec, %be ] | 
|  | %iv.dec = add i32 %iv, -1 | 
|  | %range.check = icmp sgt i32 %iv, 4 | 
|  | br i1 %range.check, label %be, label %leave | 
|  | ; CHECK:   br i1 true, label %be, label %leave.loopexit | 
|  | ; CHECK: be: | 
|  |  | 
|  | be: | 
|  | call void @side_effect() | 
|  | %be.cond = icmp sgt i32 %iv.dec, 4 | 
|  | br i1 %be.cond, label %loop, label %leave | 
|  |  | 
|  | leave: | 
|  | ret void | 
|  | } | 
|  |  | 
|  |  | 
|  | !0 = !{i32 0, i32 2147483647} |