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| ; RUN: opt %loadPolly -polly-flatten-schedule -polly-delicm-overapproximate-writes=true -polly-delicm-compute-known=true -polly-delicm -analyze < %s | FileCheck %s
;
; Verify that delicm can cope with never taken PHI incoming edges.
; The edge %body -> %body_phi is never taken, hence the access MemoryKind::PHI,
; WRITE in %body for %phi is never used.
; When mapping %phi, the write's access relation is the empty set.
;
; void func(double *A) {
; for (int j = 0; j < 2; j += 1) { /* outer */
; for (int i = 0; i < 4; i += 1) { /* reduction */
; double phi = 21.0;
; if (j < 10) // Tautology, since 0<=j<2
; phi = 42.0;
; }
; A[j] = phi;
; }
; }
;
define void @func(double* noalias nonnull %A, double* noalias nonnull %dummy) {
entry:
br label %outer.preheader
outer.preheader:
br label %outer.for
outer.for:
%j = phi i32 [0, %outer.preheader], [%j.inc, %outer.inc]
%j.cmp = icmp slt i32 %j, 2
br i1 %j.cmp, label %reduction.preheader, label %outer.exit
reduction.preheader:
%A_idx = getelementptr inbounds double, double* %A, i32 %j
br label %reduction.for
reduction.for:
%i = phi i32 [0, %reduction.preheader], [%i.inc, %reduction.inc]
br label %body
body:
%cond = icmp slt i32 %j, 10
br i1 %cond, label %alwaystaken, label %body_phi
alwaystaken:
store double 0.0, double* %dummy
br label %body_phi
body_phi:
%phi = phi double [21.0, %body], [42.0, %alwaystaken]
br label %reduction.inc
reduction.inc:
%i.inc = add nuw nsw i32 %i, 1
%i.cmp = icmp slt i32 %i.inc, 4
br i1 %i.cmp, label %reduction.for, label %reduction.exit
reduction.exit:
store double %phi, double* %A_idx
br label %outer.inc
outer.inc:
%j.inc = add nuw nsw i32 %j, 1
br label %outer.for
outer.exit:
br label %return
return:
ret void
}
; CHECK: Statistics {
; CHECK: PHI scalars mapped: 1
; CHECK: }
|