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flow-analysis and Offner's notes
From: |
Matt Wette |
Subject: |
flow-analysis and Offner's notes |
Date: |
Fri, 8 Jun 2018 17:17:55 -0700 |
User-agent: |
Mozilla/5.0 (X11; Linux x86_64; rv:52.0) Gecko/20100101 Thunderbird/52.8.0 |
Hi All,
Andy Windo's blog on flow-analysis in Guile references Offner's "Notes on Graph
Algorithms Used in Optimizing Compilers"? Anyone read this manuscript? Lemma
2.2 says, in a flow-graph, if x>>z and y>>z, then either x>>y or y>>x. The
proof
uses the argument that the path from s, the start, to z has to include both x
and y.
I'm not seeing that. Consider a graph s->x, s->y, x->z and y->z. What am I
missing?
(another example, in figure 2.1 C>>K and B>>K but C and B are not ordered.)
Ref: http://www.cs.umb.edu/~offner/files/flow_graph.pdf
Matt
- flow-analysis and Offner's notes,
Matt Wette <=