diff options
| -rw-r--r-- | src/core/arm/skyeye_common/vfp/vfpsingle.cpp | 14 |
1 files changed, 12 insertions, 2 deletions
diff --git a/src/core/arm/skyeye_common/vfp/vfpsingle.cpp b/src/core/arm/skyeye_common/vfp/vfpsingle.cpp index ae5b325f0..6b4cb8efa 100644 --- a/src/core/arm/skyeye_common/vfp/vfpsingle.cpp +++ b/src/core/arm/skyeye_common/vfp/vfpsingle.cpp @@ -1049,12 +1049,22 @@ static u32 vfp_single_fadd(ARMul_State* state, int sd, int sn, s32 m, u32 fpscr) static u32 vfp_single_fsub(ARMul_State* state, int sd, int sn, s32 m, u32 fpscr) { LOG_TRACE(Core_ARM11, "s%u = %08x", sn, sd); /* - * Subtraction is addition with one sign inverted. + * Subtraction is addition with one sign inverted. Unpack the second operand to perform FTZ if + * necessary, we can't let fadd do this because a denormal in m might get flushed to +0 in FTZ + * mode, and the resulting sign of 0 OP +0 differs between fadd and fsub. We do not need to do + * this for n because +0 OP 0 is always +0 for both fadd and fsub. */ + struct vfp_single vsm; + u32 exceptions = vfp_single_unpack(&vsm, m, fpscr); + if (exceptions & FPSCR_IDC) { + // The value was flushed to zero, re-pack it. + m = vfp_single_pack(&vsm); + } + if (m != 0x7FC00000) // Only negate if m isn't NaN. m = vfp_single_packed_negate(m); - return vfp_single_fadd(state, sd, sn, m, fpscr); + return vfp_single_fadd(state, sd, sn, m, fpscr) | exceptions; } /* |