dead_access_phi.ll
1.27 KB
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; RUN: opt %loadPolly -polly-stmt-granularity=bb -polly-simplify -analyze < %s | FileCheck %s -match-full-lines
; RUN: opt %loadPolly -polly-stmt-granularity=bb "-passes=scop(print<polly-simplify>)" -disable-output -aa-pipeline=basic-aa < %s | FileCheck %s -match-full-lines
;
; Remove a dead PHI write/read pair
; (accesses that are effectively not used)
;
; for (int j = 0; j < n; j += 1) {
; body:
; double phi = 42;
;
; body_succ:
; A[0] = 42.0;
; }
;
define void @func(i32 %n, double* noalias nonnull %A) {
entry:
br label %for
for:
%j = phi i32 [0, %entry], [%j.inc, %inc]
%j.cmp = icmp slt i32 %j, %n
br i1 %j.cmp, label %body, label %exit
body:
br label %body_succ
body_succ:
%phi = phi double [42.0, %body]
store double 42.0, double* %A
br label %inc
inc:
%j.inc = add nuw nsw i32 %j, 1
br label %for
exit:
br label %return
return:
ret void
}
; CHECK: Statistics {
; CHECK: Dead accesses removed: 2
; CHECK: Dead instructions removed: 1
; CHECK: Stmts removed: 1
; CHECK: }
; CHECK: After accesses {
; CHECK-NEXT: Stmt_body_succ
; CHECK-NEXT: MustWriteAccess := [Reduction Type: NONE] [Scalar: 0]
; CHECK-NEXT: [n] -> { Stmt_body_succ[i0] -> MemRef_A[0] };
; CHECK-NEXT: }