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| ; RUN: opt < %s -loop-reduce -S -mtriple=x86_64-unknown-unknown 2>&1 | FileCheck %s
; Provide legal integer types.
target datalayout = "n8:16:32:64"
define void @foobar(i32 %n) nounwind {
; CHECK-LABEL: foobar(
; CHECK: phi double
entry:
%cond = icmp eq i32 %n, 0 ; <i1>:0 [#uses=2]
br i1 %cond, label %return, label %bb.nph
bb.nph: ; preds = %entry
%umax = select i1 %cond, i32 1, i32 %n ; <i32> [#uses=1]
br label %bb
bb: ; preds = %bb, %bb.nph
%i.03 = phi i32 [ 0, %bb.nph ], [ %indvar.next, %bb ] ; <i32> [#uses=3]
tail call void @bar( i32 %i.03 ) nounwind
%tmp1 = uitofp i32 %i.03 to double ; <double>:1 [#uses=1]
tail call void @foo( double %tmp1 ) nounwind
%indvar.next = add nsw nuw i32 %i.03, 1 ; <i32> [#uses=2]
%exitcond = icmp eq i32 %indvar.next, %umax ; <i1> [#uses=1]
br i1 %exitcond, label %return, label %bb
return: ; preds = %bb, %entry
ret void
}
; Unable to eliminate cast because the mantissa bits for double are not enough
; to hold all of i64 IV bits.
define void @foobar2(i64 %n) nounwind {
; CHECK-LABEL: foobar2(
; CHECK-NOT: phi double
; CHECK-NOT: phi float
entry:
%cond = icmp eq i64 %n, 0 ; <i1>:0 [#uses=2]
br i1 %cond, label %return, label %bb.nph
bb.nph: ; preds = %entry
%umax = select i1 %cond, i64 1, i64 %n ; <i64> [#uses=1]
br label %bb
bb: ; preds = %bb, %bb.nph
%i.03 = phi i64 [ 0, %bb.nph ], [ %indvar.next, %bb ] ; <i64> [#uses=3]
%tmp1 = trunc i64 %i.03 to i32 ; <i32>:1 [#uses=1]
tail call void @bar( i32 %tmp1 ) nounwind
%tmp2 = uitofp i64 %i.03 to double ; <double>:2 [#uses=1]
tail call void @foo( double %tmp2 ) nounwind
%indvar.next = add nsw nuw i64 %i.03, 1 ; <i64> [#uses=2]
%exitcond = icmp eq i64 %indvar.next, %umax ; <i1> [#uses=1]
br i1 %exitcond, label %return, label %bb
return: ; preds = %bb, %entry
ret void
}
; Unable to eliminate cast due to potentional overflow.
define void @foobar3() nounwind {
; CHECK-LABEL: foobar3(
; CHECK-NOT: phi double
; CHECK-NOT: phi float
entry:
%tmp0 = tail call i32 (...) @nn( ) nounwind ; <i32>:0 [#uses=1]
%cond = icmp eq i32 %tmp0, 0 ; <i1>:1 [#uses=1]
br i1 %cond, label %return, label %bb
bb: ; preds = %bb, %entry
%i.03 = phi i32 [ 0, %entry ], [ %indvar.next, %bb ] ; <i32> [#uses=3]
tail call void @bar( i32 %i.03 ) nounwind
%tmp2 = uitofp i32 %i.03 to double ; <double>:2 [#uses=1]
tail call void @foo( double %tmp2 ) nounwind
%indvar.next = add nuw nsw i32 %i.03, 1 ; <i32>:3 [#uses=2]
%tmp4 = tail call i32 (...) @nn( ) nounwind ; <i32>:4 [#uses=1]
%exitcond = icmp ugt i32 %tmp4, %indvar.next ; <i1>:5 [#uses=1]
br i1 %exitcond, label %bb, label %return
return: ; preds = %bb, %entry
ret void
}
; Unable to eliminate cast due to overflow.
define void @foobar4() nounwind {
; CHECK-LABEL: foobar4(
; CHECK-NOT: phi double
; CHECK-NOT: phi float
entry:
br label %bb.nph
bb.nph: ; preds = %entry
br label %bb
bb: ; preds = %bb, %bb.nph
%i.03 = phi i8 [ 0, %bb.nph ], [ %indvar.next, %bb ] ; <i32> [#uses=3]
%tmp2 = sext i8 %i.03 to i32 ; <i32>:0 [#uses=1]
tail call void @bar( i32 %tmp2 ) nounwind
%tmp3 = uitofp i8 %i.03 to double ; <double>:1 [#uses=1]
tail call void @foo( double %tmp3 ) nounwind
%indvar.next = add nsw nuw i8 %i.03, 1 ; <i32> [#uses=2]
%tmp = sext i8 %indvar.next to i32
%exitcond = icmp eq i32 %tmp, 32767 ; <i1> [#uses=1]
br i1 %exitcond, label %return, label %bb
return: ; preds = %bb, %entry
ret void
}
; Unable to eliminate cast because the integer IV overflows (accum exceeds
; SINT_MAX).
define i32 @foobar5() {
; CHECK-LABEL: foobar5(
; CHECK-NOT: phi double
; CHECK-NOT: phi float
entry:
br label %loop
loop:
%accum = phi i32 [ -3220, %entry ], [ %accum.next, %loop ]
%iv = phi i32 [ 12, %entry ], [ %iv.next, %loop ]
%tmp1 = sitofp i32 %accum to double
tail call void @foo( double %tmp1 ) nounwind
%accum.next = add i32 %accum, 9597741
%iv.next = add nuw nsw i32 %iv, 1
%exitcond = icmp ugt i32 %iv, 235
br i1 %exitcond, label %exit, label %loop
exit: ; preds = %loop
ret i32 %accum.next
}
; Can eliminate if we set nsw and, thus, think that we don't overflow SINT_MAX.
define i32 @foobar6() {
; CHECK-LABEL: foobar6(
; CHECK: phi double
entry:
br label %loop
loop:
%accum = phi i32 [ -3220, %entry ], [ %accum.next, %loop ]
%iv = phi i32 [ 12, %entry ], [ %iv.next, %loop ]
%tmp1 = sitofp i32 %accum to double
tail call void @foo( double %tmp1 ) nounwind
%accum.next = add nsw i32 %accum, 9597741
%iv.next = add nuw nsw i32 %iv, 1
%exitcond = icmp ugt i32 %iv, 235
br i1 %exitcond, label %exit, label %loop
exit: ; preds = %loop
ret i32 %accum.next
}
; Unable to eliminate cast because the integer IV overflows (accum exceeds
; UINT_MAX).
define i32 @foobar7() {
; CHECK-LABEL: foobar7(
; CHECK-NOT: phi double
; CHECK-NOT: phi float
entry:
br label %loop
loop:
%accum = phi i32 [ -3220, %entry ], [ %accum.next, %loop ]
%iv = phi i32 [ 12, %entry ], [ %iv.next, %loop ]
%tmp1 = uitofp i32 %accum to double
tail call void @foo( double %tmp1 ) nounwind
%accum.next = add i32 %accum, 9597741
%iv.next = add nuw nsw i32 %iv, 1
%exitcond = icmp ugt i32 %iv, 235
br i1 %exitcond, label %exit, label %loop
exit: ; preds = %loop
ret i32 %accum.next
}
; Can eliminate if we set nuw and, thus, think that we don't overflow UINT_MAX.
define i32 @foobar8() {
; CHECK-LABEL: foobar8(
; CHECK: phi double
entry:
br label %loop
loop:
%accum = phi i32 [ -3220, %entry ], [ %accum.next, %loop ]
%iv = phi i32 [ 12, %entry ], [ %iv.next, %loop ]
%tmp1 = uitofp i32 %accum to double
tail call void @foo( double %tmp1 ) nounwind
%accum.next = add nuw i32 %accum, 9597741
%iv.next = add nuw nsw i32 %iv, 1
%exitcond = icmp ugt i32 %iv, 235
br i1 %exitcond, label %exit, label %loop
exit: ; preds = %loop
ret i32 %accum.next
}
declare void @bar(i32)
declare void @foo(double)
declare i32 @nn(...)
|