fix(vfp): correct f32/f64 rounding for ceil/floor/nearest#51
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PR #47 implemented f32 rounding pseudo-ops but had two bugs: 1. The rounding mode values for ceil (0b01) and floor (0b10) were swapped 2. All rounding modes used VCVTR.S32.F32 which always truncates toward zero, ignoring the mode parameter entirely Fix by properly manipulating the FPSCR rounding mode bits [23:22] for ceil/floor/nearest, using the non-R variant of VCVT.S32.F32 (bit[7]=0) which honours the FPSCR rounding mode, then restoring FPSCR afterward. Trunc continues to use VCVTR (the R variant). Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>
Same bug as f32: the f64 rounding encoder ignored the mode parameter and always truncated toward zero. Also ceil/floor mode values were swapped (ceil had 0b10 instead of 0b01, floor had 0b01 instead of 0b10). Applies the same FPSCR rounding-mode manipulation fix to both ARM32 and Thumb-2 f64 encoders. Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>
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Summary
ceil/floor/nearest all produced truncation — ignored rounding mode param and had ceil/floor FPSCR values swapped. Fixed both f32 and f64 encoders to manipulate FPSCR rounding bits correctly.
Test plan
🤖 Generated with Claude Code