A better fix for handling different FPU initial control words for different

ABIs:
- Store the FPU initial control word in the pcb for each thread.
- When first using the FPU, load the initial control word after restoring
  the clean state if it is not the standard control word.
- Provide a correct control word for Linux/i386 binaries under
  FreeBSD/amd64.
- Adjust the control word returned for fpugetregs()/npxgetregs() when a
  thread hasn't used the FPU yet to reflect the real initial control
  word for the current ABI.
- The Linux/i386 ABI for FreeBSD/i386 now properly sets the right control
  word instead of trashing whatever the current state of the FPU is.

Reviewed by:	bde

1 files changed, 1 insertions, 0 deletions

diff --git a/sys/amd64/ia32/ia32_signal.c b/sys/amd64/ia32/ia32_signal.c
index d3b9ae3..019faba 100644
--- a/sys/amd64/ia32/ia32_signal.c
+++ b/sys/amd64/ia32/ia32_signal.c
@@ -729,6 +729,7 @@ ia32_setregs(td, entry, stack, ps_strings)
 	pcb->pcb_es = _udatasel;
 	pcb->pcb_fs = _udatasel;
 	pcb->pcb_gs = _udatasel;
+	pcb->pcb_initial_fpucw = __INITIAL_FPUCW_I386__;
 
 	bzero((char *)regs, sizeof(struct trapframe));
 	regs->tf_rip = entry;