; RUN: opt -passes=print-access-info %s -disable-output 2>&1 | FileCheck %s ; This test verifies run-time boundary check of memory accesses. ; The original loop: ; void fastCopy(const char* src, char* op) { ; int len = 32; ; while (len > 0) { ; *(reinterpret_cast<long long*>(op)) = *(reinterpret_cast<const long long*>(src)); ; src += 8; ; op += 8; ; len -= 8; ; } ; } ; Boundaries calculations before this patch: ; (Low: %src High: (24 + %src)) ; and the actual distance between two pointers was 31, (%op - %src = 31) ; IsConflict = (24 > 31) = false -> execution is directed to the vectorized loop. ; The loop was vectorized to 4, 32 byte memory access ( <4 x i64> ), ; store a value at *%op touched memory under *%src. ;CHECK: function 'fastCopy': ;CHECK: (Low: %op High: (32 + %op)) ;CHECK: (Low: %src High: (32 + %src)) define void @fastCopy(i8* nocapture readonly %src, i8* nocapture %op) { entry: br label %while.body.preheader while.body.preheader: ; preds = %entry br label %while.body while.body: ; preds = %while.body.preheader, %while.body %len.addr.07 = phi i32 [ %sub, %while.body ], [ 32, %while.body.preheader ] %op.addr.06 = phi i8* [ %add.ptr1, %while.body ], [ %op, %while.body.preheader ] %src.addr.05 = phi i8* [ %add.ptr, %while.body ], [ %src, %while.body.preheader ] %0 = bitcast i8* %src.addr.05 to i64* %1 = load i64, i64* %0, align 8 %2 = bitcast i8* %op.addr.06 to i64* store i64 %1, i64* %2, align 8 %add.ptr = getelementptr inbounds i8, i8* %src.addr.05, i64 8 %add.ptr1 = getelementptr inbounds i8, i8* %op.addr.06, i64 8 %sub = add nsw i32 %len.addr.07, -8 %cmp = icmp sgt i32 %len.addr.07, 8 br i1 %cmp, label %while.body, label %while.end.loopexit while.end.loopexit: ; preds = %while.body br label %while.end while.end: ; preds = %while.end.loopexit, %entry ret void }