Files
Sylpheed/tools/ppc-manual/vmx/vrfip.md
sim 9bfe96e44d fix(ppc-manual): 543 dead links, from two generator bugs and wrong relative paths
- Category pages linked each family as `<slug>.md`, relative to categories/,
  where no family page lives. They now link `../<category>/<slug>.md`.
- Form pages linked a member into its *own* category directory, so every
  VMX128 sibling (`vsldoi128`) pointed at vmx128/ although its family page is
  under vmx/. They now link into the family's directory.
- Hand-written "Related" and sibling mentions linked other categories' pages
  as if they were in the same directory. 109 are retargeted through the page
  index; 29 that pointed a family page at itself (`vrefp128` on vrefp.md) and
  6 naming instructions the manual has no page for are plain text now.

Regenerated at the existing Canary pin (f21ebd49e): upstream has moved on, and
re-pinning belongs in its own change. The generator reports 0 family pages
changed and is idempotent; the only dead links left are TEMPLATE.md's
placeholders.

Co-Authored-By: Claude Opus 5 (1M context) <noreply@anthropic.com>
2026-09-16 22:37:12 +02:00

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vrfip — Vector Round to Floating-Point Integer toward +Infinity

Category: VMX (Altivec) · Form: VX · Opcode: 0x1000028a

Assembler Mnemonics

Mnemonic XML entry Flags Description
vrfip vrfip Vector Round to Floating-Point Integer toward +Infinity
vrfip128 vrfip128 Vector128 Round to Floating-Point Integer toward +Infinity

Syntax

vrfip [VD], [VB]
vrfip128 [VD], [VB]

Encoding

vrfip — form VX

  • Opcode word: 0x1000028a
  • Primary opcode (bits 05): 4
  • Extended opcode: 650
  • Synchronising: no
Bits Field Meaning
05 OPCD primary opcode (4)
610 VRT/VD destination vector register
1115 VRA/VA source A vector register
1620 VRB/VB source B vector register
2131 XO extended opcode (11 bits)

vrfip128 — form VX128_3

  • Opcode word: 0x180003b0
  • Primary opcode (bits 05): 6
  • Extended opcode: 944
  • Synchronising: no
Bits Field Meaning
05 OPCD primary opcode (6)
610 VD128l destination low 5 bits
1115 IMM 5-bit immediate
1620 VB128l source B low 5 bits
2127 XO extended opcode
2829 VD128h destination high 2 bits
3031 VB128h source B high 2 bits

Operands

Field Role Description
VB vrfip: read; vrfip128: read Source B vector register.
VD vrfip: write; vrfip128: write Destination vector register.

Register Effects

vrfip

  • Reads (always): VB
  • Reads (conditional): none
  • Writes (always): VD
  • Writes (conditional): none

vrfip128

  • Reads (always): VB
  • Reads (conditional): none
  • Writes (always): VD
  • Writes (conditional): none

Status-Register Effects

No condition-register or status-register effects.

Operation (pseudocode)

; No hand-written pseudocode for this instruction yet.
; The authoritative semantics are the Canary emitter snapshot under
; Implementation References; about half of Canary's emitters open
; with the PPC-style definition as a comment (`RD <- (RA) + (RB)`).
; Every side effect is also enumerated in the Register Effects and
; Status-Register Effects tables above.

C Translation Example

/* No hand-written C yet. Translate the Canary emitter snapshot   */
/* under Implementation References; its HIR maps directly:        */
/*   f.LoadGPR(n) / f.StoreGPR(n, v)  -> r[n] / r[n] = v          */
/*   f.LoadFPR / StoreFPR, f.LoadVR / StoreVR -> f[n], v[n]        */
/*   f.Load(ea, T), f.Store(ea, v) -> raw read / write; emitters   */
/*     wrap them in f.ByteSwap for the big-endian guest value      */
/*   f.UpdateCR(n, v)  -> CR field n from v's LOW 32 BITS vs 0     */
/*   f.LoadCA / f.StoreCA -> xer.CA;  f.StoreSAT -> vscr.SAT       */
/*   i.XO.RA, i.D.DS, ... -> the bit-fields listed under Operands  */
/* The Register Effects and Status-Register Effects tables above  */
/* enumerate every side effect a faithful translation must emit.  */

Implementation References

vrfip

Canary emitter (frozen snapshot @ f21ebd49e9)
int InstrEmit_vrfip(PPCHIRBuilder& f, const InstrData& i) {
  return InstrEmit_vrfip_(f, i.VX.VD, i.VX.VB);
}

// ── delegates to (src/xenia/cpu/ppc/ppc_emit_altivec.cc:1236) ──
int InstrEmit_vrfip_(PPCHIRBuilder& f, uint32_t vd, uint32_t vb) {
  // (VD) <- RndToFPInt32Ceil(VB)
  Value* v = f.Round(f.LoadVR(vb), ROUND_TO_POSITIVE_INFINITY);
  f.StoreVR(vd, v);
  return 0;
}

vrfip128

Canary emitter (frozen snapshot @ f21ebd49e9)
int InstrEmit_vrfip128(PPCHIRBuilder& f, const InstrData& i) {
  return InstrEmit_vrfip_(f, VX128_3_VD128, VX128_3_VB128);
}

// ── delegates to (src/xenia/cpu/ppc/ppc_emit_altivec.cc:1236) ──
int InstrEmit_vrfip_(PPCHIRBuilder& f, uint32_t vd, uint32_t vb) {
  // (VD) <- RndToFPInt32Ceil(VB)
  Value* v = f.Round(f.LoadVR(vb), ROUND_TO_POSITIVE_INFINITY);
  f.StoreVR(vd, v);
  return 0;
}

Special Cases & Edge Conditions

  • Round toward plus-infinity (ceiling). Each 32-bit float lane of VB is rounded up. 3.2 → 4.0, 3.2 → 3.0.
  • IEEE-754 binary32 output; VSCR[NJ] honoured.
  • Integer-too-big lanes are no-ops.
  • NaN and ±∞ pass through.
  • No VSCR[SAT], no FPSCR update.
  • Big-endian lane indexing.
  • VMX128 sibling vrfip128.
  • vrfim — round toward −∞ (the symmetric partner).
  • vrfin — round to nearest.
  • vrfiz — round toward zero.
  • vctsxs, vctuxs — float → fixed-point integer.

IBM Reference