Created Compiler Optimizations (markdown)
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+# Compiler Optimizations
+
+This page lists optimizations done by the compilers. Note that these are not guaranteed by the language specification.
+
+## Zero-width types in interface values
+
+Putting a zero-width type in an interface value doesn't allocate.
+
+* **gc:** 1.0+
+* **gccgo:** ?
+
+## Word-sized value in an interface value
+
+Putting a word-sized-or-less non-pointer type in an interface value doesn't allocate.
+
+* **gc:** 1.0-1.3, but *not* in 1.4+
+* **gccgo:** never
+
+## Map lookup by []byte
+
+For a map m of type map[string]T and []byte b, m[string(b)] doesn't allocate. (the temporary string copy of the byte slice isn't made)
+
+* **gc:** 1.4+
+* **gccgo:** ?
+
+## Escape analysis: foo
+
+TODO
+
+## Escape analysis: bar
+
+TODO
