This is intended to address Peter's comments wrt Alex's float-to-float conversion patches. In particular, the handling of NaNs therein, where some SNaN get converted to Inf instead of the appropriate QNaN.
I canonicalize NaNs within FloatParts much like we do with the original softfpu commonNaNT. With this, a couple of new specialize functions allows me to remove the float_class_dnan/float_class_msnan placeholders. This is based on some of Alex's work, which includes both the check-tcg and the float-to-float patches. My guess is that in the end we should order this first. But writing it this way was easier, for testing. The full tree is git://github.com/rth7680/qemu.git fpu-snan with these patches beginning at the merge at 537ab46101f5. r~ Richard Henderson (19): fpu/softfloat: Merge NO_SIGNALING_NANS definitions fpu/softfloat: Split floatXX_silence_nan from floatXX_maybe_silence_nan fpu/softfloat: Move softfloat-specialize.h below FloatParts definition fpu/softfloat: Canonicalize NaN fraction fpu/softfloat: Introduce parts_is_snan_frac fpu/softfloat: Replace float_class_dnan with parts_default_nan fpu/softfloat: Replace float_class_msnan with parts_silence_nan target/arm: Use floatX_silence_nan when we have already checked for SNaN target/arm: Remove floatX_maybe_silence_nan from conversions target/hppa: Remove floatX_maybe_silence_nan from conversions target/m68k: Use floatX_silence_nan when we have already checked for SNaN target/mips: Remove floatX_maybe_silence_nan from conversions target/riscv: Remove floatX_maybe_silence_nan from conversions target/s390x: Remove floatX_maybe_silence_nan from conversions fpu/softfloat: Use float*_silence_nan in propagateFloat*NaN fpu/softfloat: Remove floatX_maybe_silence_nan fpu/softfloat: Introduce SNAN_BIT_IS_ONE fpu/softfloat: Pass FloatClass to pickNaN fpu/softfloat: Pass FloatClass to pickNaNMulAdd fpu/softfloat-specialize.h | 621 +++++++++++++++++++--------------- include/fpu/softfloat-types.h | 1 + include/fpu/softfloat.h | 14 +- target/mips/cpu.h | 4 +- fpu/softfloat.c | 162 ++++----- target/arm/helper-a64.c | 7 +- target/arm/helper.c | 24 +- target/hppa/cpu.c | 1 - target/hppa/op_helper.c | 2 - target/m68k/softfloat.c | 3 +- target/mips/msa_helper.c | 4 - target/mips/op_helper.c | 2 - target/mips/translate_init.c | 4 +- target/ppc/fpu_helper.c | 1 - target/riscv/fpu_helper.c | 6 +- target/s390x/fpu_helper.c | 12 +- target/sh4/cpu.c | 1 - target/unicore32/cpu.c | 2 - 18 files changed, 430 insertions(+), 441 deletions(-) -- 2.17.0
