v_pk_fma_f16 GPU Native ISA AMD Vector
V PK FMA F16 Vector Packed Arithmetic
v_pk_fma_f16
Multiply two packed half-precision float inputs component-wise and add a third input component-wise using fused multiply add, and store the result…
Encoding
Verified bit-level encoding data is not yet available for this instruction.
The instruction-format classification below (VOP3P)
is well-documented and stable; exact per-target opcode/field bit positions have not
yet been imported from a verified source.
Operands
Operand details have not yet been curated for this instruction.
GFX Target Compatibility
| Target | Support |
|---|---|
| gfx1100 | ✅ Supported |
Related
More in Vector Packed Arithmetic
Reference
AMDGPU / GFX ISA
Description
Multiply two packed half-precision float inputs component-wise and add a third input component-wise using fused multiply add, and store the result into a vector register.
Semantics
declare tmp : 32'B;
tmp[15 : 0].f16 = fma(S0[15 : 0].f16, S1[15 : 0].f16, S2[15 : 0].f16);
tmp[31 : 16].f16 = fma(S0[31 : 16].f16, S1[31 : 16].f16, S2[31 : 16].f16);
D0.b32 = tmp
Example
v_pk_fma_f16 v5, v1, v2, s3A real instruction accepted by the LLVM assembler, taken verbatim from LLVM's own AMDGPU MC test suite (gfx11). Not from an AMD document, and not authored here.
Sources
- User Guide for AMDGPU Backend ↗ - LLVM Project
-
"AMD Instinct MI300" Instruction Set Architecture: Reference Guide ↗
- Advanced Micro Devices, Inc.
Reference Guide, page 266. - LLVM MC assembler tests for AMDGPU (gfx11) ↗ - LLVM Project