FSat0_1's MAXSS had the known 0 second, so a NaN came out as 0, unlike the
interpreter and the other backends, and the PSP (cpu/vfpu/prefix_sat, nan_gen).
-0.0 is now cleared by a compare and mask rather than by adding 0.0, which would
quiet a signaling NaN.
Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>
On the PSP, zeros and denormals all compare equal, a tie returns the
second operand, and the result keeps its bits (cpu/vfpu/minmax_zero,
minmax_tie, fcr31). The interpreter got the ties and NaNs right but
compared denormals as numbers, and each JIT had its own fast path with
host min/max, which returned the first operand on a tie and flushed or
not depending on the host's mode.
All cores now compare by vfpu_minmax_key(), an integer key that is 0
for a zero exponent and orders the rest by sign and magnitude, and
select the operand by it, without branching on NaN.
Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>
A new FSinCos op writes both from one argument reduction. arm64 and x64 get
both back from a single call, packed in one double; RISC-V and LoongArch make
the two calls.
Co-Authored-By: Claude Opus 5.5 (1M context) <noreply@anthropic.com>
vh2f always went to the interpreter in the IR. A new FHalfToFloat op
converts the lower or upper half of a word, and the native backends
call vfpu_h2f for it like FSin. The legacy arm64 JIT now makes the same
call instead of computing the conversion inline; vh2f is rare, and the
call is much less code.
Co-Authored-By: Claude Opus 5.5 (1M context) <noreply@anthropic.com>
These were always interpreted. They're now IR ops that the native
backends compile to calls to vfpu_exp2 and vfpu_log2, like FSin and
FAsin. vrexp2 is FNeg followed by FExp2, which is how vfpu_rexp2
computes it.
Co-Authored-By: Claude Opus 5.5 (1M context) <noreply@anthropic.com>
These went through the host's sqrt and division everywhere except the
interpreter's vrcp and vnrcp (vsqrt and vrsq there only behind
USE_VFPU_SQRT, now gone). They now always give the PSP's bits: the IR
gets FVSqrt (FSqrt stays the FPU's IEEE sqrt.s), and FRSqrt and FRecip,
which only the VFPU emits, become vfpu_rsqrt and vfpu_rcp; the IR
interpreter and the x64, arm64, RISC-V and LoongArch backends call them.
The old JITs call them directly, the ARM ones keeping the lanes in
callee-saved registers across the calls. cpu/vfpu/exact now passes on every core.
Co-Authored-By: Claude Opus 5.5 (1M context) <noreply@anthropic.com>
x86 (SQRTSS and libm alike) returns 0xffc00000 for it, the PSP 0x7fc00000.
-0 stays -0 and a NaN input comes through as it is, so only a negative
input needs the sign cleared: a compare and an xor in the x64 JITs, a
branch in the interpreters. cpu/fpu/roundmode.
Co-Authored-By: Claude Fable 5.1 <noreply@anthropic.com>
EN/NN compared the source against an uninitialized temp, usually the
previous lane's all-ones mask (a NaN), so every lane came out as NaN. NI
used a less-than compare, which is false for a NaN. TR set the bit and
then replaced it with a garbage bit from the temp. Found by
cpu/vfpu/specials.
Co-Authored-By: Claude Fable 5.1 <noreply@anthropic.com>
In the interpreter, the IR interpreter, every backend's FSign and the x86
JIT's own vsgn. Recorded in cpu/vfpu/specials.
Co-Authored-By: Claude Fable 5.1 <noreply@anthropic.com>
The NaN check compared src1 with itself, so only a NaN in src1 reached
the slow path with the hardware's integer-compare rule. A NaN in src2 went
to MINSS/MAXSS, which just return it. Compare src1 with src2, as the arm64
backend does. Caught by cpu/vfpu/minmax.
Co-Authored-By: Claude Fable 5.1 <noreply@anthropic.com>
