diff options
Diffstat (limited to 'lib/mlibc/options/rtdl/aarch64/runtime.S')
-rw-r--r-- | lib/mlibc/options/rtdl/aarch64/runtime.S | 62 |
1 files changed, 62 insertions, 0 deletions
diff --git a/lib/mlibc/options/rtdl/aarch64/runtime.S b/lib/mlibc/options/rtdl/aarch64/runtime.S new file mode 100644 index 0000000..c3e2cff --- /dev/null +++ b/lib/mlibc/options/rtdl/aarch64/runtime.S @@ -0,0 +1,62 @@ + +.global __mlibcTlsdescStatic +.hidden __mlibcTlsdescStatic +.type __mlibcTlsdescStatic,@function +__mlibcTlsdescStatic: + ldr x0, [x0, #8] + ret + +// This function depends on the Tcb layout, since it pulls out the dtv pointer +// out of the thread control block +.global __mlibcTlsdescDynamic +.hidden __mlibcTlsdescDynamic +.type __mlibcTlsdescDynamic,@function +__mlibcTlsdescDynamic: + stp x1, x2, [sp, #-16]! + ldr x0, [x0, #8] + ldp x1, x2, [x0] // tlsIndex, addend + mrs x0, tpidr_el0 // tp + ldr x0, [x0, #-104] // tp->dtvPointers + ldr x0, [x0, x1, lsl 3] // [tlsIndex] + add x0, x0, x2 // + addend + mrs x1, tpidr_el0 // tp + sub x0, x0, x1 // result - tp + ldp x1, x2, [sp], #16 + ret + +.global pltRelocateStub +pltRelocateStub: + // we need to save / restore all registers than can hold function arguments + // we do not need to save callee-saved registers as they will not be trashed by lazyRelocate + // TODO: save floating point argument registers + + stp x0, x1, [sp, #-16]! + + // pointer to PLT entry + ldr x1, [sp, #24] + ldr x0, [x16] + sub x1, x1, x0 + asr x0, x0, #3 + + // pointer GOT + sub x0, x16, #8 // &PLTGOT[1] + + stp x2, x3, [sp, #-16]! + stp x4, x5, [sp, #-16]! + stp x6, x7, [sp, #-16]! + stp x8, x30, [sp, #-16]! + + bl lazyRelocate + mov x9, x0 + + ldp x8, x30, [sp], #16 + ldp x6, x7, [sp], #16 + ldp x4, x5, [sp], #16 + ldp x2, x1, [sp], #16 + + ldp x0, x1, [sp], #16 + add sp, sp, #16 + br x9 + +.section .note.GNU-stack,"",%progbits + |