@ VFP hardware support entry point.
@
@ r0 = faulted instruction
-@ r5 = faulted PC+4
+@ r2 = faulted PC+4
@ r9 = successful return
@ r10 = vfp_state union
@ lr = failure return
.globl vfp_support_entry
vfp_support_entry:
- DBGSTR3 "instr %08x pc %08x state %p", r0, r5, r10
+ DBGSTR3 "instr %08x pc %08x state %p", r0, r2, r10
VFPFMRX r1, FPEXC @ Is the VFP enabled?
DBGSTR1 "fpexc %08x", r1
ldr r3, last_VFP_context_address
orr r1, r1, #FPEXC_ENABLE @ user FPEXC has the enable bit set
ldr r4, [r3] @ last_VFP_context pointer
- bic r2, r1, #FPEXC_EXCEPTION @ make sure exceptions are disabled
+ bic r5, r1, #FPEXC_EXCEPTION @ make sure exceptions are disabled
cmp r4, r10
beq check_for_exception @ we are returning to the same
@ process, so the registers are
@ still there. In this case, we do
@ not want to drop a pending exception.
- VFPFMXR FPEXC, r2 @ enable VFP, disable any pending
+ VFPFMXR FPEXC, r5 @ enable VFP, disable any pending
@ exceptions, so we can get at the
@ rest of it
DBGSTR1 "save old state %p", r4
cmp r4, #0
beq no_old_VFP_process
- VFPFMRX r2, FPSCR @ current status
+ VFPFMRX r5, FPSCR @ current status
VFPFMRX r6, FPINST @ FPINST (always there, rev0 onwards)
tst r1, #FPEXC_FPV2 @ is there an FPINST2 to read?
VFPFMRX r8, FPINST2, NE @ FPINST2 if needed - avoids reading
@ nonexistant reg on rev0
VFPFSTMIA r4 @ save the working registers
- add r4, r4, #8*16+4
- stmia r4, {r1, r2, r6, r8} @ save FPEXC, FPSCR, FPINST, FPINST2
+ stmia r4, {r1, r5, r6, r8} @ save FPEXC, FPSCR, FPINST, FPINST2
@ and point r4 at the word at the
@ start of the register dump
DBGSTR1 "load state %p", r10
str r10, [r3] @ update the last_VFP_context pointer
@ Load the saved state back into the VFP
- add r4, r10, #8*16+4
- ldmia r4, {r1, r2, r6, r8} @ load FPEXC, FPSCR, FPINST, FPINST2
VFPFLDMIA r10 @ reload the working registers while
@ FPEXC is in a safe state
+ ldmia r10, {r1, r5, r6, r8} @ load FPEXC, FPSCR, FPINST, FPINST2
tst r1, #FPEXC_FPV2 @ is there an FPINST2 to write?
VFPFMXR FPINST2, r8, NE @ FPINST2 if needed - avoids writing
@ nonexistant reg on rev0
VFPFMXR FPINST, r6
- VFPFMXR FPSCR, r2 @ restore status
+ VFPFMXR FPSCR, r5 @ restore status
check_for_exception:
tst r1, #FPEXC_EXCEPTION
@ out before setting an FPEXC that
@ stops us reading stuff
VFPFMXR FPEXC, r1 @ restore FPEXC last
- sub r5, r5, #4
- str r5, [sp, #S_PC] @ retry the instruction
+ sub r2, r2, #4
+ str r2, [sp, #S_PC] @ retry the instruction
mov pc, r9 @ we think we have handled things
look_for_VFP_exceptions:
tst r1, #FPEXC_EXCEPTION
bne process_exception
- VFPFMRX r2, FPSCR
- tst r2, #FPSCR_IXE @ IXE doesn't set FPEXC_EXCEPTION !
+ VFPFMRX r5, FPSCR
+ tst r5, #FPSCR_IXE @ IXE doesn't set FPEXC_EXCEPTION !
bne process_exception
@ Fall into hand on to next handler - appropriate coproc instr
process_exception:
DBGSTR "bounce"
- sub r5, r5, #4
- str r5, [sp, #S_PC] @ retry the instruction on exit from
+ sub r2, r2, #4
+ str r2, [sp, #S_PC] @ retry the instruction on exit from
@ the imprecise exception handling in
@ the support code
mov r2, sp @ nothing stacked - regdump is at TOS
.globl vfp_get_double
vfp_get_double:
- mov r0, r0, lsr #1
add pc, pc, r0, lsl #3
mov r0, r0
.irp dr,0,1,2,3,4,5,6,7,8,9,10,11,12,13,14,15
- mrrc p10, 1, r0, r1, c\dr @ fmrrd r0, r1, d\dr
+ mrrc p11, 1, r0, r1, c\dr @ fmrrd r0, r1, d\dr
mov pc, lr
.endr
+ @ virtual register 16 for compare with zero
+ mov r0, #0
+ mov r1, #0
+ mov pc, lr
+
.globl vfp_put_double
vfp_put_double:
- mov r0, r0, lsr #1
add pc, pc, r0, lsl #3
mov r0, r0
.irp dr,0,1,2,3,4,5,6,7,8,9,10,11,12,13,14,15
- mcrr p10, 1, r1, r2, c\dr @ fmrrd r1, r2, d\dr
+ mcrr p11, 1, r1, r2, c\dr @ fmdrr r1, r2, d\dr
mov pc, lr
.endr