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; RUN: opt -analyze -scalar-evolution < %s | FileCheck %s
define void @f0(i1 %c) {
; CHECK-LABEL: Classifying expressions for: @f0
entry:
%start = select i1 %c, i32 127, i32 0
%step = select i1 %c, i32 -1, i32 1
br label %loop
loop:
%loop.iv = phi i32 [ 0, %entry ], [ %loop.iv.inc, %loop ]
%iv = phi i32 [ %start, %entry ], [ %iv.next, %loop ]
; CHECK: %iv = phi i32 [ %start, %entry ], [ %iv.next, %loop ]
; CHECK-NEXT: --> {%start,+,%step}<%loop> U: [0,128) S: [0,128)
%iv.next = add i32 %iv, %step
%loop.iv.inc = add i32 %loop.iv, 1
%be.cond = icmp ne i32 %loop.iv.inc, 128
br i1 %be.cond, label %loop, label %leave
leave:
ret void
}
define void @f1(i1 %c) {
; CHECK-LABEL: Classifying expressions for: @f1
entry:
%start = select i1 %c, i32 120, i32 0
%step = select i1 %c, i32 -8, i32 8
br label %loop
loop:
%loop.iv = phi i32 [ 0, %entry ], [ %loop.iv.inc, %loop ]
%iv = phi i32 [ %start, %entry ], [ %iv.next, %loop ]
; CHECK: %iv.1 = add i32 %iv, 1
; CHECK-NEXT: --> {(1 + %start)<nuw><nsw>,+,%step}<%loop> U: [1,122) S: [1,122)
; CHECK: %iv.2 = add i32 %iv, 2
; CHECK-NEXT: --> {(2 + %start)<nuw><nsw>,+,%step}<%loop> U: [2,123) S: [2,123)
; CHECK: %iv.3 = add i32 %iv, 3
; CHECK-NEXT: --> {(3 + %start)<nuw><nsw>,+,%step}<%loop> U: [3,124) S: [3,124)
; CHECK: %iv.4 = add i32 %iv, 4
; CHECK-NEXT: --> {(4 + %start)<nuw><nsw>,+,%step}<%loop> U: [4,125) S: [4,125)
; CHECK: %iv.5 = add i32 %iv, 5
; CHECK-NEXT: --> {(5 + %start)<nuw><nsw>,+,%step}<%loop> U: [5,126) S: [5,126)
; CHECK: %iv.6 = add i32 %iv, 6
; CHECK-NEXT: --> {(6 + %start)<nuw><nsw>,+,%step}<%loop> U: [6,127) S: [6,127)
; CHECK: %iv.7 = add i32 %iv, 7
; CHECK-NEXT: --> {(7 + %start)<nuw><nsw>,+,%step}<%loop> U: [7,128) S: [7,128)
%iv.1 = add i32 %iv, 1
%iv.2 = add i32 %iv, 2
%iv.3 = add i32 %iv, 3
%iv.4 = add i32 %iv, 4
%iv.5 = add i32 %iv, 5
%iv.6 = add i32 %iv, 6
%iv.7 = add i32 %iv, 7
; CHECK: %iv.m1 = sub i32 %iv, 1
; CHECK-NEXT: --> {(-1 + %start)<nsw>,+,%step}<%loop> U: [-1,120) S: [-1,120)
; CHECK: %iv.m2 = sub i32 %iv, 2
; CHECK-NEXT: --> {(-2 + %start)<nsw>,+,%step}<%loop> U: [0,-1) S: [-2,119)
; CHECK: %iv.m3 = sub i32 %iv, 3
; CHECK-NEXT: --> {(-3 + %start)<nsw>,+,%step}<%loop> U: [-3,118) S: [-3,118)
; CHECK: %iv.m4 = sub i32 %iv, 4
; CHECK-NEXT: --> {(-4 + %start)<nsw>,+,%step}<%loop> U: [0,-3) S: [-4,117)
; CHECK: %iv.m5 = sub i32 %iv, 5
; CHECK-NEXT: --> {(-5 + %start)<nsw>,+,%step}<%loop> U: [-5,116) S: [-5,116)
; CHECK: %iv.m6 = sub i32 %iv, 6
; CHECK-NEXT: --> {(-6 + %start)<nsw>,+,%step}<%loop> U: [0,-1) S: [-6,115)
; CHECK: %iv.m7 = sub i32 %iv, 7
; CHECK-NEXT: --> {(-7 + %start)<nsw>,+,%step}<%loop> U: [-7,114) S: [-7,114)
%iv.m1 = sub i32 %iv, 1
%iv.m2 = sub i32 %iv, 2
%iv.m3 = sub i32 %iv, 3
%iv.m4 = sub i32 %iv, 4
%iv.m5 = sub i32 %iv, 5
%iv.m6 = sub i32 %iv, 6
%iv.m7 = sub i32 %iv, 7
%iv.next = add i32 %iv, %step
%loop.iv.inc = add i32 %loop.iv, 1
%be.cond = icmp sgt i32 %loop.iv, 14
br i1 %be.cond, label %leave, label %loop
leave:
ret void
}
define void @f2(i1 %c) {
; CHECK-LABEL: Classifying expressions for: @f2
entry:
%start = select i1 %c, i32 127, i32 0
%step = select i1 %c, i32 -1, i32 1
br label %loop
loop:
%loop.iv = phi i32 [ 0, %entry ], [ %loop.iv.inc, %loop ]
%iv = phi i32 [ %start, %entry ], [ %iv.next, %loop ]
%iv.sext = sext i32 %iv to i64
%iv.next = add i32 %iv, %step
; CHECK: %iv.sext = sext i32 %iv to i64
; CHECK-NEXT: --> {(sext i32 %start to i64),+,(sext i32 %step to i64)}<nsw><%loop> U: [0,128) S: [0,128)
%loop.iv.inc = add i32 %loop.iv, 1
%be.cond = icmp ne i32 %loop.iv.inc, 128
br i1 %be.cond, label %loop, label %leave
leave:
ret void
}
define void @f3(i1 %c) {
; CHECK-LABEL: Classifying expressions for: @f3
entry:
; NB! the i16 type (as opposed to i32), the choice of the constant 509
; and the trip count are all related and not arbitrary. We want an
; add recurrence that will look like it can unsign-overflow *unless*
; SCEV is able to see the correlation between the two selects feeding
; into the initial value and the step increment.
%start = select i1 %c, i16 1000, i16 0
%step = select i1 %c, i16 1, i16 509
br label %loop
loop:
%loop.iv = phi i16 [ 0, %entry ], [ %loop.iv.inc, %loop ]
%iv = phi i16 [ %start, %entry ], [ %iv.next, %loop ]
%iv.zext = zext i16 %iv to i64
; CHECK: %iv.zext = zext i16 %iv to i64
; CHECK-NEXT: --> {(zext i16 %start to i64),+,(zext i16 %step to i64)}<nuw><%loop> U: [0,64644) S: [0,64644)
%iv.next = add i16 %iv, %step
%loop.iv.inc = add i16 %loop.iv, 1
%be.cond = icmp ne i16 %loop.iv.inc, 128
br i1 %be.cond, label %loop, label %leave
leave:
ret void
}
define void @f4(i1 %c) {
; CHECK-LABEL: Classifying expressions for: @f4
; @f4() demonstrates a case where SCEV is not able to compute a
; precise range for %iv.trunc, though it should be able to, in theory.
; This is because SCEV looks into affine add recurrences only when the
; backedge taken count of the loop has the same bitwidth as the
; induction variable.
entry:
%start = select i1 %c, i32 127, i32 0
%step = select i1 %c, i32 -1, i32 1
br label %loop
loop:
%loop.iv = phi i32 [ 0, %entry ], [ %loop.iv.inc, %loop ]
%iv = phi i32 [ %start, %entry ], [ %iv.next, %loop ]
%iv.trunc = trunc i32 %iv to i16
; CHECK: %iv.trunc = trunc i32 %iv to i16
; CHECK-NEXT: --> {(trunc i32 %start to i16),+,(trunc i32 %step to i16)}<%loop> U: full-set S: full-set
%iv.next = add i32 %iv, %step
%loop.iv.inc = add i32 %loop.iv, 1
%be.cond = icmp ne i32 %loop.iv.inc, 128
br i1 %be.cond, label %loop, label %leave
leave:
ret void
}
define void @f5(i1 %c) {
; CHECK-LABEL: Classifying expressions for: @f5
entry:
%start = select i1 %c, i32 127, i32 0
%step = select i1 %c, i32 -1, i32 1
br label %loop
loop:
%loop.iv = phi i16 [ 0, %entry ], [ %loop.iv.inc, %loop ]
%iv = phi i32 [ %start, %entry ], [ %iv.next, %loop ]
%iv.trunc = trunc i32 %iv to i16
; CHECK: %iv.trunc = trunc i32 %iv to i16
; CHECK-NEXT: --> {(trunc i32 %start to i16),+,(trunc i32 %step to i16)}<%loop> U: [0,128) S: [0,128)
%iv.next = add i32 %iv, %step
%loop.iv.inc = add i16 %loop.iv, 1
%be.cond = icmp ne i16 %loop.iv.inc, 128
br i1 %be.cond, label %loop, label %leave
leave:
ret void
}
define void @f6(i1 %c) {
; CHECK-LABEL: Classifying expressions for: @f6
entry:
%start = select i1 %c, i32 127, i32 0
%step = select i1 %c, i32 -2, i32 0
br label %loop
loop:
%loop.iv = phi i16 [ 0, %entry ], [ %loop.iv.inc, %loop ]
%iv = phi i32 [ %start, %entry ], [ %iv.next, %loop ]
; CHECK: %iv = phi i32 [ %start, %entry ], [ %iv.next, %loop ]
; CHECK-NEXT: --> {%start,+,(1 + %step)<nuw><nsw>}<%loop> U: [0,128) S: [0,128)
%step.plus.one = add i32 %step, 1
%iv.next = add i32 %iv, %step.plus.one
%iv.sext = sext i32 %iv to i64
; CHECK: %iv.sext = sext i32 %iv to i64
; CHECK-NEXT: --> {(sext i32 %start to i64),+,(1 + (sext i32 %step to i64))<nuw><nsw>}<nsw><%loop> U: [0,128) S: [0,128)
%loop.iv.inc = add i16 %loop.iv, 1
%be.cond = icmp ne i16 %loop.iv.inc, 128
br i1 %be.cond, label %loop, label %leave
leave:
ret void
}
define void @f7(i1 %c) {
; CHECK-LABEL: Classifying expressions for: @f7
entry:
%start = select i1 %c, i32 127, i32 0
%step = select i1 %c, i32 -1, i32 1
br label %loop
loop:
%loop.iv = phi i16 [ 0, %entry ], [ %loop.iv.inc, %loop ]
%iv = phi i32 [ %start, %entry ], [ %iv.next, %loop ]
%iv.trunc = trunc i32 %iv to i16
; CHECK: %iv.trunc = trunc i32 %iv to i16
; CHECK-NEXT: --> {(trunc i32 %start to i16),+,(trunc i32 %step to i16)}<%loop> U: [0,128) S: [0,128)
%iv.next = add i32 %iv, %step
%iv.trunc.plus.one = add i16 %iv.trunc, 1
; CHECK: %iv.trunc.plus.one = add i16 %iv.trunc, 1
; CHECK-NEXT: --> {(1 + (trunc i32 %start to i16))<nuw><nsw>,+,(trunc i32 %step to i16)}<%loop> U: [1,129) S: [1,129)
%iv.trunc.plus.two = add i16 %iv.trunc, 2
; CHECK: %iv.trunc.plus.two = add i16 %iv.trunc, 2
; CHECK-NEXT: --> {(2 + (trunc i32 %start to i16))<nuw><nsw>,+,(trunc i32 %step to i16)}<%loop> U: [2,130) S: [2,130)
%loop.iv.inc = add i16 %loop.iv, 1
%be.cond = icmp ne i16 %loop.iv.inc, 128
br i1 %be.cond, label %loop, label %leave
leave:
ret void
}
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