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| ; RUN: opt %loadPolly -polly-stmt-granularity=bb -polly-simplify -analyze < %s | FileCheck %s -match-full-lines
;
; Do not remove the scalar value write of %i.trunc in inner.for.
; It is used by body.
; %i.trunc is synthesizable in inner.for, so some code might think it is
; synthesizable everywhere such that no scalar write would be needed.
;
; Note that -polly-simplify rightfully removes %inner.cond. It should
; not have been added to the instruction list in the first place.
;
define void @func(i32 %n, i32* noalias nonnull %A) {
entry:
br label %for
for:
%j = phi i32 [0, %entry], [%j.inc, %inc]
%j.cmp = icmp slt i32 %j, %n
%zero = sext i32 0 to i64
br i1 %j.cmp, label %inner.for, label %exit
; This loop has some unusual properties:
; * It has a known iteration count (1), therefore SCoP-compatible.
; * %i.trunc is synthesizable within the loop ({1,+,1}<%while.body>).
; * %i.trunc is not synthesizable outside of the loop, because its value is
; unknown when exiting.
; (should be 1, but ScalarEvolution currently seems unable to derive that)
;
; ScalarEvolution currently seems to not able to handle the %zero.
; If it becomes more intelligent, there might be other such loop constructs.
inner.for:
%i = phi i64 [%zero, %for], [%i.inc, %inner.for]
%i.inc = add nuw nsw i64 %i, 1
%i.trunc = trunc i64 %i.inc to i32
%i.and = and i32 %i.trunc, 6
%inner.cond = icmp eq i32 %i.and, 0
br i1 %inner.cond, label %body, label %inner.for
body:
store i32 %i.trunc, i32* %A
br label %inc
inc:
%j.inc = add nuw nsw i32 %j, 1
br label %for
exit:
br label %return
return:
ret void
}
; CHECK: After accesses {
; CHECK-NEXT: Stmt_inner_for
; CHECK-NEXT: MustWriteAccess := [Reduction Type: NONE] [Scalar: 1]
; CHECK-NEXT: [n] -> { Stmt_inner_for[i0, i1] -> MemRef_i_trunc[] };
; CHECK-NEXT: Stmt_body
; CHECK-NEXT: MustWriteAccess := [Reduction Type: NONE] [Scalar: 0]
; CHECK-NEXT: [n] -> { Stmt_body[i0] -> MemRef_A[0] };
; CHECK-NEXT: ReadAccess := [Reduction Type: NONE] [Scalar: 1]
; CHECK-NEXT: [n] -> { Stmt_body[i0] -> MemRef_i_trunc[] };
; CHECK-NEXT: }
|