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git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@45377 91177308-0d34-0410-b5e6-96231b3b80d8
This commit is contained in:
Chris Lattner 2007-12-28 04:42:05 +00:00
parent 650d5053bf
commit 166a268656

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@ -463,4 +463,23 @@ entry:
ret int %tmp3
}
//===---------------------------------------------------------------------===//
"basicaa" should know how to look through "or" instructions that act like add
instructions. For example in this code, the x*4+1 is turned into x*4 | 1, and
basicaa can't analyze the array subscript, leading to duplicated loads in the
generated code:
void test(int X, int Y, int a[]) {
int i;
for (i=2; i<1000; i+=4) {
a[i+0] = a[i-1+0]*a[i-2+0];
a[i+1] = a[i-1+1]*a[i-2+1];
a[i+2] = a[i-1+2]*a[i-2+2];
a[i+3] = a[i-1+3]*a[i-2+3];
}
}
//===---------------------------------------------------------------------===//