From 89742c2c3fe8121a3795c8ead9dc6f5809eddbaa Mon Sep 17 00:00:00 2001 From: Chris Lattner Date: Thu, 3 Dec 2009 07:43:46 +0000 Subject: [PATCH] expand note. git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@90429 91177308-0d34-0410-b5e6-96231b3b80d8 --- lib/Target/README.txt | 15 +++++++++++++++ 1 file changed, 15 insertions(+) diff --git a/lib/Target/README.txt b/lib/Target/README.txt index 2d513c8cc3a..c788360df63 100644 --- a/lib/Target/README.txt +++ b/lib/Target/README.txt @@ -1734,5 +1734,20 @@ if.end: And functionattrs doesn't realize that the p.0 load points to function local memory. +Also, functionattrs doesn't know about memcpy/memset. This function should be +marked readnone, since it only twiddles local memory, but functionattrs doesn't +handle memset/memcpy/memmove aggressively: + +struct X { int *p; int *q; }; +int foo() { + int i = 0, j = 1; + struct X x, y; + int **p; + y.p = &i; + x.q = &j; + p = __builtin_memcpy (&x, &y, sizeof (int *)); + return **p; +} + //===---------------------------------------------------------------------===// -- 2.34.1