Fix FPU_CVT_W_S: truncate toward zero and saturate like R5900 CVT.W.S - #215
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Fix FPU_CVT_W_S: truncate toward zero and saturate like R5900 CVT.W.S#215TheTharin wants to merge 1 commit into
TheTharin wants to merge 1 commit into
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The macro used nearbyintf(), which follows the host rounding mode (round-to-nearest by default) and has no overflow handling. R5900 CVT.W.S always truncates toward zero and clamps out-of-range results to INT32_MAX/INT32_MIN, matching the PCSX2 interpreter's CVT_W (pcsx2/FPU.cpp) and the C cast semantics PS2 compilers rely on when emitting cvt.w.s for (int)float casts. Adds FpuMacros tests covering truncation, host-rounding-mode independence, and overflow saturation including the +/-2^31 edges.
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The macro used
nearbyintf(), which follows the host rounding mode (round-to-nearest by default) and has no overflow handling. R5900 CVT.W.S always truncates toward zero and clamps out-of-range results toINT32_MAX/INT32_MIN, matching the PCSX2 interpreter's CVT_W (pcsx2/FPU.cpp) and the C cast semantics PS2 compilers rely on when emittingcvt.w.sfor(int)floatcasts.Divergence example: game code doing
(int)2.7fcurrently gets 3 instead of 2.Found while recompiling Rogue Galaxy (SCUS-97490) — the game's main ELF alone contains 1013
cvt.w.sinstructions.Adds FpuMacros tests covering truncation, host-rounding-mode independence, and overflow saturation including the
+/-2^31edges.Related:
#162 — adds the first FPU test suite in the repo (covers the CVT.W.S macro only).