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|
; RUN: opt %loadPolly -polly-scops -analyze < %s | FileCheck %s
;
; This checks that the no-wraps checks will be computed fast as some example
; already showed huge slowdowns even though the inbounds and nsw flags were
; all in place.
;
; // Inspired by itrans8x8 in transform8x8.c from the ldecode benchmark.
; void fast(char *A, char N, char M) {
; for (char i = 0; i < 8; i++) {
; short index0 = (short)(i + N);
; #ifdef fast
; short index1 = (index0 * 1) + (short)M;
; #else
; short index1 = (index0 * 16) + (short)M;
; #endif
; A[index1]++;
; }
; }
;
; CHECK: Function: fast
; CHECK: Function: slow
;
target datalayout = "e-m:e-i64:64-f80:128-n8:16:32:64-S128"
define void @fast(i8* %A, i8 %N, i8 %M) {
entry:
br label %for.cond
for.cond: ; preds = %for.inc, %entry
%indvars.iv = phi i8 [ %indvars.iv.next, %for.inc ], [ 0, %entry ]
%exitcond = icmp ne i8 %indvars.iv, 8
br i1 %exitcond, label %for.body, label %for.end
for.body: ; preds = %for.cond
%tmp3 = add nsw i8 %indvars.iv, %N
%tmp3ext = sext i8 %tmp3 to i16
;%mul = mul nsw i16 %tmp3ext, 16
%Mext = sext i8 %M to i16
%add2 = add nsw i16 %tmp3ext, %Mext
%arrayidx = getelementptr inbounds i8, i8* %A, i16 %add2
%tmp4 = load i8, i8* %arrayidx, align 4
%inc = add nsw i8 %tmp4, 1
store i8 %inc, i8* %arrayidx, align 4
br label %for.inc
for.inc: ; preds = %for.body
%indvars.iv.next = add nuw nsw i8 %indvars.iv, 1
br label %for.cond
for.end: ; preds = %for.cond
ret void
}
define void @slow(i8* %A, i8 %N, i8 %M) {
entry:
br label %for.cond
for.cond: ; preds = %for.inc, %entry
%indvars.iv = phi i8 [ %indvars.iv.next, %for.inc ], [ 0, %entry ]
%exitcond = icmp ne i8 %indvars.iv, 8
br i1 %exitcond, label %for.body, label %for.end
for.body: ; preds = %for.cond
%tmp3 = add nsw i8 %indvars.iv, %N
%tmp3ext = sext i8 %tmp3 to i16
%mul = mul nsw i16 %tmp3ext, 16
%Mext = sext i8 %M to i16
%add2 = add nsw i16 %mul, %Mext
%arrayidx = getelementptr inbounds i8, i8* %A, i16 %add2
%tmp4 = load i8, i8* %arrayidx, align 4
%inc = add nsw i8 %tmp4, 1
store i8 %inc, i8* %arrayidx, align 4
br label %for.inc
for.inc: ; preds = %for.body
%indvars.iv.next = add nuw nsw i8 %indvars.iv, 1
br label %for.cond
for.end: ; preds = %for.cond
ret void
}
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