Integer Subtraction Arithmetic

Subtract one integer operand from another of matching or implied width.

Vendor-Neutral Definition

d = a - b, evaluated at the operand's integer width.
⚠️ Cross-vendor mappings describe semantic relationships and are not guaranteed one-to-one compiler translations.
equivalent with restrictions Both compute d = a - b; AMDGPU again splits scalar (whole-wavefront) and per-lane vector forms where PTX has one generic sub.
Property NVIDIA PTX AMDGPU
Instruction sub v_sub_u32, s_sub_u32
ISA Layer Virtual Native
Data Types f32, f64, s16, s32, s64, u16, u32, u64 u32
Version / Target Introduced PTX ISA 1.0 gfx942/gfx1100

Important Differences

  • AMDGPU exposes separate scalar (s_sub_u32) and vector (v_sub_u32) instructions, each fixed to a specific bit-width; PTX's sub is one family covering s16/s32/s64/u16/u32/u64/f32/f64 via a type modifier.
  • Borrow-out is read from SCC (scalar) or VCC (vector) on AMDGPU rather than a PTX '.cc' carry-out modifier.

Source Evidence

Verification method: documentation