assume_gep_bounds.ll
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; RUN: opt %loadPolly -polly-scops -analyze < %s | FileCheck %s
; RUN: opt %loadPolly -polly-function-scops -analyze < %s | FileCheck %s
; void foo(float A[][20][30], long n, long m, long p) {
; for (long i = 0; i < n; i++)
; for (long j = 0; j < m; j++)
; for (long k = 0; k < p; k++)
; A[i][j][k] = i + j + k;
; }
; For the above code we want to assume that all memory accesses are within the
; bounds of the array A. In C (and LLVM-IR) this is not required, such that out
; of bounds accesses are valid. However, as such accesses are uncommon, cause
; complicated dependence pattern and as a result make dependence analysis more
; costly and may prevent or hinder useful program transformations, we assume
; absence of out-of-bound accesses. To do so we derive the set of parameter
; values for which our assumption holds.
; CHECK: Assumed Context
; CHECK-NEXT: [n, m, p] -> { :
; CHECK-DAG: p <= 30
; CHECK-DAG: and
; CHECK-DAG: m <= 20
; CHECK: }
target datalayout = "e-m:e-i64:64-f80:128-n8:16:32:64-S128"
define void @foo([20 x [30 x float]]* %A, i64 %n, i64 %m, i64 %p) {
entry:
br label %for.cond
for.cond: ; preds = %for.inc13, %entry
%i.0 = phi i64 [ 0, %entry ], [ %inc14, %for.inc13 ]
%cmp = icmp slt i64 %i.0, %n
br i1 %cmp, label %for.body, label %for.end15
for.body: ; preds = %for.cond
br label %for.cond1
for.cond1: ; preds = %for.inc10, %for.body
%j.0 = phi i64 [ 0, %for.body ], [ %inc11, %for.inc10 ]
%cmp2 = icmp slt i64 %j.0, %m
br i1 %cmp2, label %for.body3, label %for.end12
for.body3: ; preds = %for.cond1
br label %for.cond4
for.cond4: ; preds = %for.inc, %for.body3
%k.0 = phi i64 [ 0, %for.body3 ], [ %inc, %for.inc ]
%cmp5 = icmp slt i64 %k.0, %p
br i1 %cmp5, label %for.body6, label %for.end
for.body6: ; preds = %for.cond4
%add = add nsw i64 %i.0, %j.0
%add7 = add nsw i64 %add, %k.0
%conv = sitofp i64 %add7 to float
%arrayidx9 = getelementptr inbounds [20 x [30 x float]], [20 x [30 x float]]* %A, i64 %i.0, i64 %j.0, i64 %k.0
store float %conv, float* %arrayidx9, align 4
br label %for.inc
for.inc: ; preds = %for.body6
%inc = add nsw i64 %k.0, 1
br label %for.cond4
for.end: ; preds = %for.cond4
br label %for.inc10
for.inc10: ; preds = %for.end
%inc11 = add nsw i64 %j.0, 1
br label %for.cond1
for.end12: ; preds = %for.cond1
br label %for.inc13
for.inc13: ; preds = %for.end12
%inc14 = add nsw i64 %i.0, 1
br label %for.cond
for.end15: ; preds = %for.cond
ret void
}