From 6798310a0465c859d663bd8161797581c19ffefd Mon Sep 17 00:00:00 2001 From: Luke Kenneth Casson Leighton Date: Thu, 8 Aug 2019 06:26:12 +0100 Subject: [PATCH] add recip-sqrt as separate proposal --- ztrans_proposal.mdwn | 5 +++++ 1 file changed, 5 insertions(+) diff --git a/ztrans_proposal.mdwn b/ztrans_proposal.mdwn index fd294697a..2c941cdb6 100644 --- a/ztrans_proposal.mdwn +++ b/ztrans_proposal.mdwn @@ -19,6 +19,7 @@ Extension subsets: * **Zfhyp**: hyperbolic/inverse-hyperbolic. sinh, cosh, tanh, asinh, acosh, atanh (can be synthesised - see below) * **ZftransAdv**: much more complex to implement in hardware +* **Zfrsqrt**: Reciprocal square-root. Minimum recommended requirements for 3D: Zftrans, Ztrigpi, Zarctrigpi, Zarctrignpi @@ -32,6 +33,9 @@ Zarctrignpi * Errors **MUST** be repeatable. * How about three Platform Specifications? 3D, UNIX and Embedded? +* Reciprocal Square-root is in its own separate extension (Zfrsqrt) as + it is desirable on its own by other implementors. This to be evaluated. + # List of 2-arg opcodes @@ -48,6 +52,7 @@ FHYPOT | hypotenuse | rd = sqrt(rs1^2 + rs2^2) | Zftrans [[!table data=""" opcode | Description | pseudo-code | Extension | +FRSQRT | Reciprocal Square-root | rd = sqrt(rs1) | Zfrsqrt | FCBRT | Cube Root | rd = pow(rs1, 3) | Zftrans | FEXP2 | power-of-2 | rd = pow(2, rs1) | Zftrans | FLOG2 | log2 | rd = log2(rs1) | Zftrans | -- 2.30.2