s_and_not1_saveexec_b64 GPU Native ISA AMD Scalar

Scalar Arithmetic

s_and_not1_saveexec_b64

Calculate bitwise AND on the scalar input and the negation of the EXEC mask, store the calculated result into the EXEC mask, set SCC iff the…

Also written as s_andn2_saveexec_b64. AMD's machine-readable ISA specification lists this name for the same instruction.

Encoding

Binary Layout (AMD CDNA 5)
101111101
31:23
SDST
22:16
00110001
15:8
SSRC0
7:0
 

The ENC_SOP1 layout from AMD's machine-readable ISA specification (AMD CDNA 5). Opcode 49 in OP rebuilds 0xBE803100, an identifier AMD lists for this encoding. The same in the other 3 generations that define it.

Format SOP1
Width 32 bits
Opcode 49
Identifier 0xBE803100

Operands

  • SDST
    Written. Any scalar GPR operand including VCC and NULL. Data format: Unsigned 64-bit integral data. (OPR_SREG, FMT_NUM_U64)
  • SSRC0
    Read. All scalar operands. Covers all operands that are allowed as scalar sources. Data format: Unsigned 64-bit integral data. (OPR_SSRC, FMT_NUM_U64)

In AMD's order, as its machine-readable ISA specification lists them for the ENC_SOP1 encoding (AMD CDNA 5).

GFX Target Compatibility

TargetSupport
gfx1100✅ Supported

Related

More in Scalar Arithmetic

Reference

AMDGPU / GFX ISA

Description

Calculate bitwise AND on the scalar input and the negation of the EXEC mask, store the calculated result into the EXEC mask, set SCC iff the calculated result is nonzero and store the original value of the EXEC mask into the scalar destination register.

Example

s_and_not1_saveexec_b64 vcc, 0.5

A real instruction accepted by the LLVM assembler, taken verbatim from LLVM's own AMDGPU MC test suite. Not from an AMD document, and not authored here.

Sources