Files
linux-kernel-module-cheat/userland/arch/aarch64/floating_point.S
Ciro Santilli 六四事件 法轮功 0263c21557 userland: add assembly support
Move arm assembly cheat here, and start some work on x86 cheat as well.
2019-05-05 00:00:00 +00:00

61 lines
1.2 KiB
ArmAsm

/* https://github.com/cirosantilli/arm-assembly-cheat#advanced-simd-instructions */
#include "common.h"
ENTRY
/* 1.5 + 2.5 == 4.0
* using 64-bit double immediates.
*/
fmov d0, 1.5
fmov d1, 2.5
fadd d2, d0, d1
fmov d3, 4.0
/* Unlike VFP vcmp, this stores the status
* automatically in the main CPSR.
*/
fcmp d2, d3
ASSERT(beq)
/* Now with a memory stored value. */
.data
my_double_0:
.double 1.5
my_double_1:
.double 2.5
my_double_sum_expect:
.double 4.0
.text
ldr d0, my_double_0
ldr d1, my_double_1
fadd d2, d0, d1
ldr d3, my_double_sum_expect
fcmp d2, d3
ASSERT(beq)
/* Now in 32-bit. */
fmov s0, 1.5
fmov s1, 2.5
fadd s2, s0, s1
fmov s3, 4.0
fcmp s2, s3
ASSERT(beq)
/* TODO why? What's the point of q then?
* Error: operand mismatch -- `fmov q0,1.5'
*/
#if 0
fmov q0, 1.5
#endif
/* Much like integers, immediates are constrained to
* fit in 32-byte instructions. TODO exact rules.
*
* Assembly here would fail with:
*
* Error: invalid floating-point constant at operand 2
*/
#if 0
fmov d0, 1.23456798
#endif
EXIT