arch/m68k/fpsp040/x_unfl.S
Source file repositories/reference/linux-study-clean/arch/m68k/fpsp040/x_unfl.S
File Facts
- System
- Linux kernel
- Corpus path
arch/m68k/fpsp040/x_unfl.S- Extension
.S- Size
- 6961 bytes
- Lines
- 269
- Domain
- Architecture Layer
- Bucket
- arch/m68k
- Inferred role
- Architecture Layer: arch/m68k
- Status
- atlas-only
Why This File Exists
CPU and platform-specific kernel glue: boot entry, traps, syscall entry, interrupts, page tables, context switch, and low-level barriers.
- CPU and platform-specific kernel glue: boot entry, traps, syscall entry, interrupts, page tables, context switch, and low-level barriers.
Dependency Surface
fpsp.h
Detected Declarations
function CMDREG3Bfunction FPCR_MODE
Annotated Snippet
bfextu CMDREG3B(%a6){#6:#3},%d0 |get dest reg no
bclrb %d0,FPR_DIRTY_BITS(%a6) |clr dest dirty bit
bsrl b1238_fix |test for bug1238 case
movel USER_FPSR(%a6),FPSR_SHADOW(%a6)
orl #sx_mask,E_BYTE(%a6)
no_e3_1:
moveml USER_DA(%a6),%d0-%d1/%a0-%a1
fmovemx USER_FP0(%a6),%fp0-%fp3
fmoveml USER_FPCR(%a6),%fpcr/%fpsr/%fpiar
frestore (%a7)+
unlk %a6
bral real_unfl
|
| It is possible to have either inex2 or inex1 exceptions with the
| unfl. If the inex enable bit is set in the FPCR, and either
| inex2 or inex1 occurred, we must clean up and branch to the
| real inex handler.
|
ck_inex:
moveb FPCR_ENABLE(%a6),%d0
andb FPSR_EXCEPT(%a6),%d0
andib #0x3,%d0
beqs unfl_done
|
| Inexact enabled and reported, and we must take an inexact exception
|
take_inex:
btstb #E3,E_BYTE(%a6)
beqs no_e3_2
|
| Clear dirty bit on dest resister in the frame before branching
| to b1238_fix.
|
bfextu CMDREG3B(%a6){#6:#3},%d0 |get dest reg no
bclrb %d0,FPR_DIRTY_BITS(%a6) |clr dest dirty bit
bsrl b1238_fix |test for bug1238 case
movel USER_FPSR(%a6),FPSR_SHADOW(%a6)
orl #sx_mask,E_BYTE(%a6)
no_e3_2:
moveb #INEX_VEC,EXC_VEC+1(%a6)
moveml USER_DA(%a6),%d0-%d1/%a0-%a1
fmovemx USER_FP0(%a6),%fp0-%fp3
fmoveml USER_FPCR(%a6),%fpcr/%fpsr/%fpiar
frestore (%a7)+
unlk %a6
bral real_inex
unfl_done:
bclrb #E3,E_BYTE(%a6)
beqs e1_set |if set then branch
|
| Clear dirty bit on dest resister in the frame before branching
| to b1238_fix.
|
bfextu CMDREG3B(%a6){#6:#3},%d0 |get dest reg no
bclrb %d0,FPR_DIRTY_BITS(%a6) |clr dest dirty bit
bsrl b1238_fix |test for bug1238 case
movel USER_FPSR(%a6),FPSR_SHADOW(%a6)
orl #sx_mask,E_BYTE(%a6)
moveml USER_DA(%a6),%d0-%d1/%a0-%a1
fmovemx USER_FP0(%a6),%fp0-%fp3
fmoveml USER_FPCR(%a6),%fpcr/%fpsr/%fpiar
frestore (%a7)+
unlk %a6
bral fpsp_done
e1_set:
moveml USER_DA(%a6),%d0-%d1/%a0-%a1
fmovemx USER_FP0(%a6),%fp0-%fp3
fmoveml USER_FPCR(%a6),%fpcr/%fpsr/%fpiar
Annotation
- Immediate include surface: `fpsp.h`.
- Detected declarations: `function CMDREG3B`, `function FPCR_MODE`.
- Atlas domain: Architecture Layer / arch/m68k.
- Implementation status: atlas-only.
Implementation Notes
- This generated page is the file-by-file coverage layer; curated subsystem chapters should link here when they synthesize a multi-file control flow.
- Core OS pages should be promoted from atlas-only to deep-reviewed when they explain data structures, invariants, locking, lifecycle, and C implementation snippets.
- Driver-family pages are intentionally pattern-oriented unless they are part of the selected PCIe/NVMe representative device path.