madc GPU Virtual ISA NVIDIA

madc Extended-Precision Integer Arithmetic Instructions

madc{.hi,.lo}{.cc}.type d, a, b, c;

Multiplies two values, extracts either the high or low part of the result, and adds a third value along with carry-in.

Encoding

PTX is a virtual instruction set. It has no single, stable native binary encoding - the compiler lowers this instruction to different native machine code depending on the selected NVIDIA target architecture (compute capability). This page intentionally shows no bit-diagram; see the target/version requirements below for what governs how this instruction compiles.
PTX ISA Version Introduced PTX ISA 3.0
Minimum Target sm_10

Syntax Forms

One mnemonic covers many type / state-space / scope / modifier combinations - each row below is an independently valid form.

Syntax Data Types State Space(s) Modifiers Min. Target Description
madc{.hi,.lo}{.cc}.type d, a, b, c; sm_10 Multiplies two values, extracts either the high or low part of the result, and adds a third value along with carry-in. (see the official PTX ISA docs for the full description)

Operands

  • d
    Destination register
  • a
    Source operand
  • b
    Source operand
  • c
    Source operand

At a Glance

Data Types -

Related

More in Extended-Precision Integer Arithmetic Instructions

Reference

NVIDIA PTX ISA

Description

Multiplies two values, extracts either the high or low part of the result, and adds a third value along with carry-in. Writes the result to the destination register and optionally writes the carry-out from the addition into the condition code register.

Semantics

t = a * b; d = t<63..32> + c + CC.CF; // for .hi variant d = t<31..0> + c + CC.CF; // for .lo variant

Examples

// extended-precision multiply:  [r3,r2,r1,r0] = [r5,r4] * [r7,r6]
mul.lo.u32     r0,r4,r6;      // r0=(r4*r6).[31:0], no carry-out
mul.hi.u32     r1,r4,r6;      // r1=(r4*r6).[63:32], no carry-out
mad.lo.cc.u32  r1,r5,r6,r1;   // r1+=(r5*r6).[31:0], may carry-out
madc.hi.u32    r2,r5,r6,0;    // r2 =(r5*r6).[63:32]+carry-in,
                              // no carry-out
// (truncated - see the official PTX ISA docs for the full example)

Reproduced from NVIDIA's official PTX ISA documentation for technical accuracy.

Sources