diff --git a/src/cmd/compile/internal/ssa/README.md b/src/cmd/compile/internal/ssa/README.md
index 4483c2c85f..833bf1ddc9 100644
--- a/src/cmd/compile/internal/ssa/README.md
+++ b/src/cmd/compile/internal/ssa/README.md
@@ -184,6 +184,19 @@ compile passes, making it easy to see what each pass does to a particular
 program. You can also click on values and blocks to highlight them, to help
 follow the control flow and values.
 
+The value specified in GOSSAFUNC can also be a package-qualified function
+name, e.g. 
+
+	GOSSAFUNC=blah.Foo go build
+    
+This will match any function named "Foo" within a package whose final
+suffix is "blah" (e.g. something/blah.Foo, anotherthing/extra/blah.Foo).
+
+If non-HTML dumps are needed, append a "+" to the GOSSAFUNC value
+and dumps will be written to stdout:
+
+	GOSSAFUNC=Bar+ go build
+
 <!---
 TODO: need more ideas for this section
 -->
diff --git a/src/cmd/compile/internal/ssa/compile.go b/src/cmd/compile/internal/ssa/compile.go
index 8aae04f2ec..cd8eba405d 100644
--- a/src/cmd/compile/internal/ssa/compile.go
+++ b/src/cmd/compile/internal/ssa/compile.go
@@ -297,6 +297,11 @@ enables time reporting for all phases
     -d=ssa/prove/debug=2
 sets debugging level to 2 in the prove pass
 
+Be aware that when "/debug=X" is applied to a pass, some passes
+will emit debug output for all functions, and other passes will
+only emit debug output for functions that match the current
+GOSSAFUNC value.
+
 Multiple flags can be passed at once, by separating them with
 commas. For example: