This series modifies the original ColdFire FPU implementation to use floatx80 instead of float64 internally as this is the native datatype for 680x0. I didn't keep the float64 type for ColdFire, but if someone thinks it's required I can update this series in this way.
The series also adds the FPU status and control registers. The floatx80 datatype used here is not exactly the same as the one used by 680x0 for its extended precision data type, because normally the signaling bit of 680x0 NAN is the MSB of the mantissa minus one and in floatx80 it is the MSB. We also add the gdb server parts to read the new FPU registers. A strange thing happens here: while the gdb client running remotely from a debian etch-m68k has no issue working with 96bit FPU registers (the 680x0 extended precision data type), new gdbs (from a debian unstable and gdb for cross-compiled environment) don't expect this FPU registers size. But it seems like a bug in gdb, not in this implementation. v5: rebase, some patches are now part of master call cpu_m68k_set_fpcr() in XX_fpu_gdb_set_reg() generate unimplemented data type exception for packed data type, and only on coldfire, for extended data type remove QEMU_FPCR/QEMU_FPSR rework gen_op_fmove_fcr() replace cpu_abort(...) by qemu_log_mask(LOG_UNIMP, ...) add a patch to reset FPU registers add a patch to manage FPU registers in ucontext (linux-user) Note: I will replace floatx80 by a floatx96, later, once we have a working linux-user qemu-m68k. v4: this is only a subset of v3 add a patch to move fmove CR to a function use "FPReg *" instead of FP0/FP1 temporaries fcmp/ftst take old FPSR register from parameters and return the new one add R-b from Richard v3: fix fsave opcode Add comment to define "unnormalized" number Correctly define pickNaN() v2: complete rework of the series force single precision in ColdFire mode add "forced" precision instructions (fsmove, fdmove, fsadd, ...) fixed Fcc. Laurent Vivier (6): target-m68k: move fmove CR to a function target-m68k: initialize FPU registers target-m68k: use floatx80 internally target-m68k: define 96bit FP registers for gdb on 680x0 target-m68k: add FPCR and FPSR target-m68k,linux-user: manage FP registers in ucontext configure | 2 +- gdb-xml/m68k-fp.xml | 21 + linux-user/signal.c | 41 ++ target/m68k/cpu.c | 9 +- target/m68k/cpu.h | 58 ++- target/m68k/fpu_helper.c | 180 ++++++--- target/m68k/helper.c | 77 +++- target/m68k/helper.h | 38 +- target/m68k/qregs.def | 1 - target/m68k/translate.c | 983 ++++++++++++++++++++++++++++++++--------------- 10 files changed, 1025 insertions(+), 385 deletions(-) create mode 100644 gdb-xml/m68k-fp.xml -- 2.9.4