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| ; NOTE: Assertions have been autogenerated by utils/update_test_checks.py
; RUN: opt < %s -indvars -loop-deletion -simplifycfg -S | FileCheck %s
; Test that we can evaluate the exit values of various expression types. Since
; these loops all have predictable exit values we can replace the use outside
; of the loop with a closed-form computation.
define i32 @polynomial_constant() {
; <label>:0
; CHECK-LABEL: @polynomial_constant(
; CHECK-NEXT: Out:
; CHECK-NEXT: ret i32 500500
;
br label %Loop
Loop: ; preds = %Loop, %0
%A1 = phi i32 [ 0, %0 ], [ %A2, %Loop ] ; <i32> [#uses=3]
%B1 = phi i32 [ 0, %0 ], [ %B2, %Loop ] ; <i32> [#uses=1]
%A2 = add i32 %A1, 1 ; <i32> [#uses=1]
%B2 = add i32 %B1, %A1 ; <i32> [#uses=2]
%C = icmp eq i32 %A1, 1000 ; <i1> [#uses=1]
br i1 %C, label %Out, label %Loop
Out: ; preds = %Loop
ret i32 %B2
}
define i32 @NSquare(i32 %N) {
; <label>:0
; CHECK-LABEL: @NSquare(
; CHECK-NEXT: Out:
; CHECK-NEXT: [[Y:%.*]] = mul i32 [[N:%.*]], [[N]]
; CHECK-NEXT: ret i32 [[Y]]
;
br label %Loop
Loop: ; preds = %Loop, %0
%X = phi i32 [ 0, %0 ], [ %X2, %Loop ] ; <i32> [#uses=4]
%X2 = add i32 %X, 1 ; <i32> [#uses=1]
%c = icmp eq i32 %X, %N ; <i1> [#uses=1]
br i1 %c, label %Out, label %Loop
Out: ; preds = %Loop
%Y = mul i32 %X, %X ; <i32> [#uses=1]
ret i32 %Y
}
define i32 @NSquareOver2(i32 %N) {
; <label>:0
; CHECK-LABEL: @NSquareOver2(
; CHECK-NEXT: Out:
; CHECK-NEXT: [[TMP0:%.*]] = zext i32 [[N:%.*]] to i33
; CHECK-NEXT: [[TMP1:%.*]] = add i32 [[N]], -1
; CHECK-NEXT: [[TMP2:%.*]] = zext i32 [[TMP1]] to i33
; CHECK-NEXT: [[TMP3:%.*]] = mul i33 [[TMP0]], [[TMP2]]
; CHECK-NEXT: [[TMP4:%.*]] = lshr i33 [[TMP3]], 1
; CHECK-NEXT: [[TMP5:%.*]] = trunc i33 [[TMP4]] to i32
; CHECK-NEXT: [[TMP6:%.*]] = add i32 [[N]], [[TMP5]]
; CHECK-NEXT: [[TMP7:%.*]] = add i32 [[TMP6]], 15
; CHECK-NEXT: ret i32 [[TMP7]]
;
br label %Loop
Loop: ; preds = %Loop, %0
%X = phi i32 [ 0, %0 ], [ %X2, %Loop ] ; <i32> [#uses=3]
%Y = phi i32 [ 15, %0 ], [ %Y2, %Loop ] ; <i32> [#uses=1]
%Y2 = add i32 %Y, %X ; <i32> [#uses=2]
%X2 = add i32 %X, 1 ; <i32> [#uses=1]
%c = icmp eq i32 %X, %N ; <i1> [#uses=1]
br i1 %c, label %Out, label %Loop
Out: ; preds = %Loop
ret i32 %Y2
}
define i32 @strength_reduced() {
; <label>:0
; CHECK-LABEL: @strength_reduced(
; CHECK-NEXT: Out:
; CHECK-NEXT: ret i32 500500
;
br label %Loop
Loop: ; preds = %Loop, %0
%A1 = phi i32 [ 0, %0 ], [ %A2, %Loop ] ; <i32> [#uses=3]
%B1 = phi i32 [ 0, %0 ], [ %B2, %Loop ] ; <i32> [#uses=1]
%A2 = add i32 %A1, 1 ; <i32> [#uses=1]
%B2 = add i32 %B1, %A1 ; <i32> [#uses=2]
%C = icmp eq i32 %A1, 1000 ; <i1> [#uses=1]
br i1 %C, label %Out, label %Loop
Out: ; preds = %Loop
ret i32 %B2
}
define i32 @chrec_equals() {
; CHECK-LABEL: @chrec_equals(
; CHECK-NEXT: entry:
; CHECK-NEXT: ret i32 101
;
entry:
br label %no_exit
no_exit: ; preds = %no_exit, %entry
%i0 = phi i32 [ 0, %entry ], [ %i1, %no_exit ] ; <i32> [#uses=3]
%ISq = mul i32 %i0, %i0 ; <i32> [#uses=1]
%i1 = add i32 %i0, 1 ; <i32> [#uses=2]
%tmp.1 = icmp ne i32 %ISq, 10000 ; <i1> [#uses=1]
br i1 %tmp.1, label %no_exit, label %loopexit
loopexit: ; preds = %no_exit
ret i32 %i1
}
define i16 @cast_chrec_test() {
; <label>:0
; CHECK-LABEL: @cast_chrec_test(
; CHECK-NEXT: Out:
; CHECK-NEXT: ret i16 1000
;
br label %Loop
Loop: ; preds = %Loop, %0
%A1 = phi i32 [ 0, %0 ], [ %A2, %Loop ] ; <i32> [#uses=2]
%B1 = trunc i32 %A1 to i16 ; <i16> [#uses=2]
%A2 = add i32 %A1, 1 ; <i32> [#uses=1]
%C = icmp eq i16 %B1, 1000 ; <i1> [#uses=1]
br i1 %C, label %Out, label %Loop
Out: ; preds = %Loop
ret i16 %B1
}
define i32 @linear_div_fold() {
; CHECK-LABEL: @linear_div_fold(
; CHECK-NEXT: entry:
; CHECK-NEXT: ret i32 34
;
entry:
br label %loop
loop: ; preds = %loop, %entry
%i = phi i32 [ 4, %entry ], [ %i.next, %loop ] ; <i32> [#uses=3]
%i.next = add i32 %i, 8 ; <i32> [#uses=1]
%RV = udiv i32 %i, 2 ; <i32> [#uses=1]
%c = icmp ne i32 %i, 68 ; <i1> [#uses=1]
br i1 %c, label %loop, label %loopexit
loopexit: ; preds = %loop
ret i32 %RV
}
define i32 @unroll_phi_select_constant_nonzero(i32 %arg1, i32 %arg2) {
; CHECK-LABEL: @unroll_phi_select_constant_nonzero(
; CHECK-NEXT: entry:
; CHECK-NEXT: ret i32 [[ARG2:%.*]]
;
entry:
br label %loop
loop:
%i = phi i32 [ 0, %entry ], [ %i.next, %loop ]
%selector = phi i32 [%arg1, %entry], [%arg2, %loop]
%i.next = add nsw nuw i32 %i, 1
%c = icmp ult i32 %i, 4
br i1 %c, label %loop, label %loopexit
loopexit:
ret i32 %selector
}
declare i32 @f()
; After LCSSA formation, there's no LCSSA phi for %f since it isn't directly
; used outside the loop, and thus we can't directly replace %selector w/ %f.
define i32 @neg_unroll_phi_select_constant_nonzero(i32 %arg) {
; CHECK-LABEL: @neg_unroll_phi_select_constant_nonzero(
; CHECK-NEXT: entry:
; CHECK-NEXT: br label [[LOOP:%.*]]
; CHECK: loop:
; CHECK-NEXT: [[I:%.*]] = phi i32 [ 0, [[ENTRY:%.*]] ], [ [[I_NEXT:%.*]], [[LOOP]] ]
; CHECK-NEXT: [[SELECTOR:%.*]] = phi i32 [ [[ARG:%.*]], [[ENTRY]] ], [ [[F:%.*]], [[LOOP]] ]
; CHECK-NEXT: [[F]] = call i32 @f()
; CHECK-NEXT: [[I_NEXT]] = add nuw nsw i32 [[I]], 1
; CHECK-NEXT: [[C:%.*]] = icmp ult i32 [[I]], 4
; CHECK-NEXT: br i1 [[C]], label [[LOOP]], label [[LOOPEXIT:%.*]]
; CHECK: loopexit:
; CHECK-NEXT: [[SELECTOR_LCSSA:%.*]] = phi i32 [ [[SELECTOR]], [[LOOP]] ]
; CHECK-NEXT: ret i32 [[SELECTOR_LCSSA]]
;
entry:
br label %loop
loop:
%i = phi i32 [ 0, %entry ], [ %i.next, %loop ]
%selector = phi i32 [%arg, %entry], [%f, %loop]
%f = call i32 @f()
%i.next = add nsw nuw i32 %i, 1
%c = icmp ult i32 %i, 4
br i1 %c, label %loop, label %loopexit
loopexit:
ret i32 %selector
}
define i32 @unroll_phi_select_constant_zero(i32 %arg1, i32 %arg2) {
; CHECK-LABEL: @unroll_phi_select_constant_zero(
; CHECK-NEXT: entry:
; CHECK-NEXT: ret i32 [[ARG1:%.*]]
;
entry:
br label %loop
loop:
%i = phi i32 [ 0, %entry ], [ %i.next, %loop ]
%selector = phi i32 [%arg1, %entry], [%arg2, %loop]
%i.next = add i32 %i, 1
%c = icmp ne i32 %i, 0
br i1 %c, label %loop, label %loopexit
loopexit:
ret i32 %selector
}
define i32 @unroll_phi_select(i32 %arg1, i32 %arg2, i16 %len) {
; CHECK-LABEL: @unroll_phi_select(
; CHECK-NEXT: entry:
; CHECK-NEXT: [[LENGTH:%.*]] = zext i16 [[LEN:%.*]] to i32
; CHECK-NEXT: ret i32 [[ARG2:%.*]]
;
entry:
%length = zext i16 %len to i32
br label %loop
loop:
%i = phi i32 [ -1, %entry ], [ %i.next, %loop ]
%selector = phi i32 [%arg1, %entry], [%arg2, %loop]
%i.next = add nsw i32 %i, 1
%c = icmp slt i32 %i, %length
br i1 %c, label %loop, label %loopexit
loopexit:
ret i32 %selector
}
|