add ipc extension

[libreriscv.git] / isa_conflict_resolution.mdwn

diff --git a/isa_conflict_resolution.mdwn b/isa_conflict_resolution.mdwn
index 03aef29efbfe6eb2a79c1762ba0553136209ad4e..b0a14fcde5f96ffda158311f6f03de728af9f622 100644 (file)
--- a/isa_conflict_resolution.mdwn
+++ b/isa_conflict_resolution.mdwn
@@ -558,6 +558,12 @@ The following conversation exerpts are taken from the ISA-dev discussion
 > instruction decode must be unambiguous, it merely expands every opcode with
 > extra bits from a "select" CSR.
 
+## (5) Krste Asanovic on clarification of use of opcode space
+
+> A CPU is even free to reuse some standard extension encoding space for
+> non-standard extensions provided it does not claim to implement that
+> standard extension.
+
 # References
 
 * <https://groups.google.com/a/groups.riscv.org/forum/#!topic/isa-dev/7bbwSIW5aqM>