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|
; 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}
|
