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; RUN: opt %loadPolly -basic-aa -polly-scops -analyze < %s | FileCheck %s
; RUN: opt %loadPolly -basic-aa -polly-function-scops -analyze < %s | FileCheck %s
; ModuleID = 'scalar_to_array.ll'
target datalayout = "e-p:64:64:64-i1:8:8-i8:8:8-i16:16:16-i32:32:32-i64:64:64-f32:32:32-f64:64:64-v64:64:64-v128:128:128-a0:0:64-s0:64:64-f80:128:128-n8:16:32:64"
@A = common global [1024 x float] zeroinitializer, align 8
; Terminating loops without side-effects will be optimzied away, hence
; detecting a scop would be pointless.
; CHECK-NOT: Function: empty
; Function Attrs: nounwind
define i32 @empty() #0 {
entry:
fence seq_cst
br label %for.cond
for.cond: ; preds = %for.inc, %entry
%indvar = phi i64 [ %indvar.next, %for.inc ], [ 0, %entry ]
%exitcond = icmp ne i64 %indvar, 1024
br i1 %exitcond, label %for.body, label %return
for.body: ; preds = %for.cond
br label %for.inc
for.inc: ; preds = %for.body
%indvar.next = add i64 %indvar, 1
br label %for.cond
return: ; preds = %for.cond
fence seq_cst
ret i32 0
}
; CHECK-LABEL: Function: array_access
; Function Attrs: nounwind
define i32 @array_access() #0 {
entry:
fence seq_cst
br label %for.cond
for.cond: ; preds = %for.inc, %entry
%indvar = phi i64 [ %indvar.next, %for.inc ], [ 0, %entry ]
%exitcond = icmp ne i64 %indvar, 1024
br i1 %exitcond, label %for.body, label %return
for.body: ; preds = %for.cond
%arrayidx = getelementptr [1024 x float], [1024 x float]* @A, i64 0, i64 %indvar
%float = uitofp i64 %indvar to float
store float %float, float* %arrayidx
br label %for.inc
; CHECK: Stmt_for_body
; CHECK-NOT: ReadAccess
; CHECK: MustWriteAccess := [Reduction Type: NONE] [Scalar: 0]
; CHECK-NEXT: { Stmt_for_body[i0] -> MemRef_A[i0] };
for.inc: ; preds = %for.body
%indvar.next = add i64 %indvar, 1
br label %for.cond
return: ; preds = %for.cond
fence seq_cst
ret i32 0
}
; Function Attrs: nounwind
; CHECK-LABEL: Function: intra_scop_dep
define i32 @intra_scop_dep() #0 {
entry:
fence seq_cst
br label %for.cond
for.cond: ; preds = %for.inc, %entry
%indvar = phi i64 [ %indvar.next, %for.inc ], [ 0, %entry ]
%exitcond = icmp ne i64 %indvar, 1024
br i1 %exitcond, label %for.body.a, label %return
for.body.a: ; preds = %for.cond
%arrayidx = getelementptr [1024 x float], [1024 x float]* @A, i64 0, i64 %indvar
%scalar = load float, float* %arrayidx
br label %for.body.b
; CHECK: Stmt_for_body_a
; CHECK: ReadAccess := [Reduction Type: NONE] [Scalar: 0]
; CHECK-NEXT: { Stmt_for_body_a[i0] -> MemRef_A[i0] };
; CHECK: MustWriteAccess := [Reduction Type: NONE] [Scalar: 1]
; CHECK-NEXT: { Stmt_for_body_a[i0] -> MemRef_scalar[] };
for.body.b: ; preds = %for.body.a
%arrayidx2 = getelementptr [1024 x float], [1024 x float]* @A, i64 0, i64 %indvar
%float = uitofp i64 %indvar to float
%sum = fadd float %scalar, %float
store float %sum, float* %arrayidx2
br label %for.inc
; CHECK: Stmt_for_body_b
; CHECK: ReadAccess := [Reduction Type: NONE] [Scalar: 1]
; CHECK-NEXT: { Stmt_for_body_b[i0] -> MemRef_scalar[] };
; CHECK: MustWriteAccess := [Reduction Type: NONE] [Scalar: 0]
; CHECK-NEXT: { Stmt_for_body_b[i0] -> MemRef_A[i0] };
for.inc: ; preds = %for.body.b
%indvar.next = add i64 %indvar, 1
br label %for.cond
return: ; preds = %for.cond
fence seq_cst
ret i32 0
}
; It is not possible to have a scop which accesses a scalar element that is
; a global variable. All global variables are pointers containing possibly
; a single element. Hence they do not need to be handled anyways.
; Please note that this is still required when scalar to array rewritting is
; disabled.
; CHECK-LABEL: Function: use_after_scop
; Function Attrs: nounwind
define i32 @use_after_scop() #0 {
entry:
%scalar.s2a = alloca float
fence seq_cst
br label %for.head
for.head: ; preds = %for.inc, %entry
%indvar = phi i64 [ %indvar.next, %for.inc ], [ 0, %entry ]
br label %for.body
for.body: ; preds = %for.head
%arrayidx = getelementptr [1024 x float], [1024 x float]* @A, i64 0, i64 %indvar
%scalar = load float, float* %arrayidx
store float %scalar, float* %scalar.s2a
; Escaped uses are still required to be rewritten to stack variable.
; CHECK: Stmt_for_body
; CHECK: ReadAccess := [Reduction Type: NONE] [Scalar: 0]
; CHECK-NEXT: { Stmt_for_body[i0] -> MemRef_A[i0] };
; CHECK: MustWriteAccess := [Reduction Type: NONE] [Scalar: 0]
; CHECK-NEXT: { Stmt_for_body[i0] -> MemRef_scalar_s2a[0] };
br label %for.inc
for.inc: ; preds = %for.body
%indvar.next = add i64 %indvar, 1
%exitcond = icmp ne i64 %indvar.next, 1024
br i1 %exitcond, label %for.head, label %for.after
for.after: ; preds = %for.inc
%scalar.loadoutside = load float, float* %scalar.s2a
fence seq_cst
%return_value = fptosi float %scalar.loadoutside to i32
br label %return
return: ; preds = %for.after
ret i32 %return_value
}
; We currently do not transform scalar references, that have only read accesses
; in the scop. There are two reasons for this:
;
; o We don't introduce additional memory references which may yield to compile
; time overhead.
; o For integer values, such a translation may block the use of scalar
; evolution on those values.
;
; CHECK-LABEL: Function: before_scop
; Function Attrs: nounwind
define i32 @before_scop() #0 {
entry:
br label %preheader
preheader: ; preds = %entry
%scalar = fadd float 4.000000e+00, 5.000000e+00
fence seq_cst
br label %for.cond
for.cond: ; preds = %for.inc, %preheader
%indvar = phi i64 [ %indvar.next, %for.inc ], [ 0, %preheader ]
%exitcond = icmp ne i64 %indvar, 1024
br i1 %exitcond, label %for.body, label %return
for.body: ; preds = %for.cond
%arrayidx = getelementptr [1024 x float], [1024 x float]* @A, i64 0, i64 %indvar
store float %scalar, float* %arrayidx
br label %for.inc
; CHECK: Stmt_for_body
; CHECK: MustWriteAccess := [Reduction Type: NONE] [Scalar: 0]
; CHECK-NEXT: { Stmt_for_body[i0] -> MemRef_A[i0] };
for.inc: ; preds = %for.body
%indvar.next = add i64 %indvar, 1
br label %for.cond
return: ; preds = %for.cond
fence seq_cst
ret i32 0
}
attributes #0 = { nounwind }
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