checkasm: arm: Ignore changes to bits 0-4 and 7 of FPSCR

These bits are set by exceptions in NEON instructions.

Also print the differing bits when FPSCR is clobbered,
and use bic instead of lsl, for clearing the topmost bits.

Signed-off-by: Martin Storsjö <martin@martin.st>
This commit is contained in:
Martin Storsjö 2016-07-17 13:31:06 +03:00
parent 59aeed93e4
commit 37961044c6

View File

@ -40,7 +40,7 @@ const register_init, align=3
endconst
const error_message_fpscr
.asciz "failed to preserve register FPSCR"
.asciz "failed to preserve register FPSCR, changed bits: %x"
error_message_gpr:
.asciz "failed to preserve register r%d"
error_message_vfp:
@ -106,11 +106,13 @@ function checkasm_checked_call_\variant, export=1
.endr
.purgem check_reg_vfp
fmrx r0, FPSCR
fmrx r1, FPSCR
ldr r3, [sp, #8]
eor r0, r0, r3
eor r1, r1, r3
@ Ignore changes in bits 0-4 and 7
bic r1, r1, #0x9f
@ Ignore changes in the topmost 5 bits
lsls r0, r0, #5
bics r1, r1, #0xf8000000
bne 3f
.endif