On 07/05/20 02:42, Joseph Myers wrote: > Among the various bugs in the x87 floating-point emulation that show > up through a combination of glibc testing and code inspection, there > are several in the implementations of the fxtract and fscale > instructions. This series fixes those bugs. > > Bugs in other instructions, and bugs relating to floating-point > exceptions and flag setting, will be addressed separately. In > particular, while some of these patches add code that sets exception > flags in the softfloat state, it's generally the case that the x87 > emulation ignores exceptions in that state rather than propagating > them to the status word (and to generating traps where appropriate). > I intend to address that missing propagation of exceptions in a > subsequent patch series; until it's addressed, the code setting > exceptions won't actually do anything useful. (There is also code in > the x87 emulation, including that of fscale, that would result in > spurious exceptions being set from a naive propagation of exceptions > from the softfloat state, and thus will need updating to avoid > propagating inappropriate exceptions when such propagation is > implemented.) > > Joseph Myers (5): > target/i386: implement special cases for fxtract > target/i386: fix fscale handling of signaling NaN > target/i386: fix fscale handling of invalid exponent encodings > target/i386: fix fscale handling of infinite exponents > target/i386: fix fscale handling of rounding precision > > target/i386/fpu_helper.c | 59 +++++++++++++- > tests/tcg/i386/test-i386-fscale.c | 108 ++++++++++++++++++++++++++ > tests/tcg/i386/test-i386-fxtract.c | 120 +++++++++++++++++++++++++++++ > 3 files changed, 285 insertions(+), 2 deletions(-) > create mode 100644 tests/tcg/i386/test-i386-fscale.c > create mode 100644 tests/tcg/i386/test-i386-fxtract.c >
Queued, thanks. Paolo
