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|
; RUN: opt -S -loop-vectorize -force-vector-width=8 -force-vector-interleave=1 < %s | FileCheck %s -check-prefix=VF8
; RUN: opt -S -loop-vectorize -force-vector-width=1 -force-vector-interleave=4 < %s | FileCheck %s -check-prefix=VF1
target datalayout = "e-m:e-i64:64-f80:128-n8:16:32:64-S128"
; Given a loop with an induction variable which is being
; truncated/extended using casts that had been proven to
; be redundant under a runtime test, we want to make sure
; that these casts, do not get vectorized/scalarized/widened.
; This is the case for inductions whose SCEV expression is
; of the form "ExtTrunc(%phi) + %step", where "ExtTrunc"
; can be a result of the IR sequences we check below.
;
; See also pr30654.
;
; Case1: Check the following induction pattern:
;
; %p.09 = phi i32 [ 0, %for.body.lr.ph ], [ %add, %for.body ]
; %sext = shl i32 %p.09, 24
; %conv = ashr exact i32 %sext, 24
; %add = add nsw i32 %conv, %step
;
; This is the case in the following code:
;
; void doit1(int n, int step) {
; int i;
; char p = 0;
; for (i = 0; i < n; i++) {
; a[i] = p;
; p = p + step;
; }
; }
;
; The "ExtTrunc" IR sequence here is:
; "%sext = shl i32 %p.09, 24"
; "%conv = ashr exact i32 %sext, 24"
; We check that it does not appear in the vector loop body, whether
; we vectorize or scalarize the induction.
; In the case of widened induction, this means that the induction phi
; is directly used, without shl/ashr on the way.
; VF8-LABEL: @doit1
; VF8: vector.body:
; VF8: %vec.ind = phi <8 x i32>
; VF8: store <8 x i32> %vec.ind
; VF8: middle.block:
; VF1-LABEL: @doit1
; VF1: vector.body:
; VF1-NOT: %{{.*}} = shl i32
; VF1: middle.block:
@a = common local_unnamed_addr global [250 x i32] zeroinitializer, align 16
define void @doit1(i32 %n, i32 %step) {
entry:
%cmp7 = icmp sgt i32 %n, 0
br i1 %cmp7, label %for.body.lr.ph, label %for.end
for.body.lr.ph:
%wide.trip.count = zext i32 %n to i64
br label %for.body
for.body:
%indvars.iv = phi i64 [ 0, %for.body.lr.ph ], [ %indvars.iv.next, %for.body ]
%p.09 = phi i32 [ 0, %for.body.lr.ph ], [ %add, %for.body ]
%sext = shl i32 %p.09, 24
%conv = ashr exact i32 %sext, 24
%arrayidx = getelementptr inbounds [250 x i32], [250 x i32]* @a, i64 0, i64 %indvars.iv
store i32 %conv, i32* %arrayidx, align 4
%add = add nsw i32 %conv, %step
%indvars.iv.next = add nuw nsw i64 %indvars.iv, 1
%exitcond = icmp eq i64 %indvars.iv.next, %wide.trip.count
br i1 %exitcond, label %for.end.loopexit, label %for.body
for.end.loopexit:
br label %for.end
for.end:
ret void
}
; Case2: Another variant of the above pattern is where the induction variable
; is used only for address compuation (i.e. it is a GEP index) and therefore
; the induction is not vectorized but rather only the step is widened.
;
; This is the case in the following code, where the induction variable 'w_ix'
; is only used to access the array 'in':
;
; void doit2(int *in, int *out, size_t size, size_t step)
; {
; int w_ix = 0;
; for (size_t offset = 0; offset < size; ++offset)
; {
; int w = in[w_ix];
; out[offset] = w;
; w_ix += step;
; }
; }
;
; The "ExtTrunc" IR sequence here is similar to the previous case:
; "%sext = shl i64 %w_ix.012, 32
; %idxprom = ashr exact i64 %sext, 32"
; We check that it does not appear in the vector loop body, whether
; we widen or scalarize the induction.
; In the case of widened induction, this means that the induction phi
; is directly used, without shl/ashr on the way.
; VF8-LABEL: @doit2
; VF8: vector.body:
; VF8: %vec.ind = phi <8 x i64>
; VF8: %{{.*}} = extractelement <8 x i64> %vec.ind
; VF8: middle.block:
; VF1-LABEL: @doit2
; VF1: vector.body:
; VF1-NOT: %{{.*}} = shl i64
; VF1: middle.block:
;
define void @doit2(i32* nocapture readonly %in, i32* nocapture %out, i64 %size, i64 %step) {
entry:
%cmp9 = icmp eq i64 %size, 0
br i1 %cmp9, label %for.cond.cleanup, label %for.body.lr.ph
for.body.lr.ph:
br label %for.body
for.cond.cleanup.loopexit:
br label %for.cond.cleanup
for.cond.cleanup:
ret void
for.body:
%w_ix.011 = phi i64 [ 0, %for.body.lr.ph ], [ %add, %for.body ]
%offset.010 = phi i64 [ 0, %for.body.lr.ph ], [ %inc, %for.body ]
%sext = shl i64 %w_ix.011, 32
%idxprom = ashr exact i64 %sext, 32
%arrayidx = getelementptr inbounds i32, i32* %in, i64 %idxprom
%0 = load i32, i32* %arrayidx, align 4
%arrayidx1 = getelementptr inbounds i32, i32* %out, i64 %offset.010
store i32 %0, i32* %arrayidx1, align 4
%add = add i64 %idxprom, %step
%inc = add nuw i64 %offset.010, 1
%exitcond = icmp eq i64 %inc, %size
br i1 %exitcond, label %for.cond.cleanup.loopexit, label %for.body
}
; Case3: Lastly, check also the following induction pattern:
;
; %p.09 = phi i32 [ %val0, %scalar.ph ], [ %add, %for.body ]
; %conv = and i32 %p.09, 255
; %add = add nsw i32 %conv, %step
;
; This is the case in the following code:
;
; int a[N];
; void doit3(int n, int step) {
; int i;
; unsigned char p = 0;
; for (i = 0; i < n; i++) {
; a[i] = p;
; p = p + step;
; }
; }
;
; The "ExtTrunc" IR sequence here is:
; "%conv = and i32 %p.09, 255".
; We check that it does not appear in the vector loop body, whether
; we vectorize or scalarize the induction.
; VF8-LABEL: @doit3
; VF8: vector.body:
; VF8: %vec.ind = phi <8 x i32>
; VF8: store <8 x i32> %vec.ind
; VF8: middle.block:
; VF1-LABEL: @doit3
; VF1: vector.body:
; VF1-NOT: %{{.*}} = and i32
; VF1: middle.block:
define void @doit3(i32 %n, i32 %step) {
entry:
%cmp7 = icmp sgt i32 %n, 0
br i1 %cmp7, label %for.body.lr.ph, label %for.end
for.body.lr.ph:
%wide.trip.count = zext i32 %n to i64
br label %for.body
for.body:
%indvars.iv = phi i64 [ 0, %for.body.lr.ph ], [ %indvars.iv.next, %for.body ]
%p.09 = phi i32 [ 0, %for.body.lr.ph ], [ %add, %for.body ]
%conv = and i32 %p.09, 255
%arrayidx = getelementptr inbounds [250 x i32], [250 x i32]* @a, i64 0, i64 %indvars.iv
store i32 %conv, i32* %arrayidx, align 4
%add = add nsw i32 %conv, %step
%indvars.iv.next = add nuw nsw i64 %indvars.iv, 1
%exitcond = icmp eq i64 %indvars.iv.next, %wide.trip.count
br i1 %exitcond, label %for.end.loopexit, label %for.body
for.end.loopexit:
br label %for.end
for.end:
ret void
}
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