gecko-dev/xpcom/reflect/xptcall/md/unix/xptcinvoke_asm_ipf64.s

147 строки
4.8 KiB
ArmAsm

// Select C numeric constant
.radix C
// for 64 bit mode, use .psr abi64
.psr abi64
// little endian
.psr lsb
// Section has executable code
.section .text, "ax","progbits"
// procedure named 'NS_InvokeByIndex'
.proc NS_InvokeByIndex
// manual bundling
.explicit
// extern "C" uint32_t
// invoke_copy_to_stack(uint64_t* d,
// const uint32_t paramCount, nsXPTCVariant* s)
.global invoke_copy_to_stack
// .exclass invoke_copy_to_stack, @fullyvisible
.type invoke_copy_to_stack,@function
// .exclass NS_InvokeByIndex, @fullyvisible
.type NS_InvokeByIndex,@function
// XPTC_InvokeByIndex(nsISupports* that, uint32_t methodIndex,
// uint32_t paramCount, nsXPTCVariant* params);
NS_InvokeByIndex::
.prologue
.save ar.pfs, r37
// allocate 4 input args, 6 local args, and 8 output args
alloc r37 = ar.pfs, 4, 6, 8, 0 // M
nop.i 0 ;; // I
// unwind table already knows gp, no need to specify anything
add r39 = 0, gp // A
.save rp, r36
mov r36 = rp // I
.vframe r38
add r38 = 0, sp ;; // A
// We first calculate the amount of extra memory stack space required
// for the arguments, and register storage.
// We then call invoke_copy_to_stack() to write the argument contents
// to the specified memory regions.
// We then copy the integer arguments to integer registers, and floating
// arguments to float registers.
// Lastly we load the virtual table jump pointer, and call the target
// subroutine.
// in0 : that
// in1 : methodIndex
// in2 : paramCount
// in3 : params
// stack frame size is 16 + (8 * even(paramCount)) + 64 + 64
// 16 byte frame header
// 8 * even(paramCount) memory argument area
// 64 bytes integer register area
// 64 bytes float register area
// This scheme makes sure stack fram size is a multiple of 16
.body
add r10 = 8, r0 // A
// r41 points to float register area
add r41 = -64, sp // A
// r40 points to int register area
add r40 = -128, sp ;; // A
add out1 = 0, r40 // A
add out2 = 0, r41 // A
tbit.z p14,p15 = in2,0 ;; // I
// compute 8 * even(paramCount)
(p14) shladd r11 = in2, 3, r0 ;; // A
(p15) shladd r11 = in2, 3, r10 ;; // A
sub out0 = r40, r11 ;; // A
// advance the stack frame
add sp = -16, out0 // A
add out3 = 0, in2 // A
add out4 = 0, in3 // A
// branch to invoke_copy_to_stack
br.call.sptk.few rp = invoke_copy_to_stack ;; // B
// restore gp
add gp = 0, r39 // A
add out0 = 0, in0 // A
// load the integer and float registers
ld8 out1 = [r40], 8 // M
ldfd f8 = [r41], 8 ;; // M
ld8 out2 = [r40], 8 // M
ldfd f9 = [r41], 8 ;; // M
ld8 out3 = [r40], 8 // M
ldfd f10 = [r41], 8 ;; // M
ld8 out4 = [r40], 8 // M
ldfd f11 = [r41], 8 ;; // M
ld8 out5 = [r40], 8 // M
ldfd f12 = [r41], 8 ;; // M
// 16 * methodIndex
shladd r11 = in1, 4, r0 // A
ld8 out6 = [r40], 8 // M
ldfd f13 = [r41], 8 ;; // M
ld8 out7 = [r40], 8 // M
ldfd f14 = [r41], 8 // M
add r8 = 0, in0 ;; // A
// look up virtual base table and dispatch to target subroutine
// This section assumes 64 bit pointer mode, and virtual base table
// layout from the ABI http://www.codesourcery.com/cxx-abi/abi.html
// load base table
ld8 r8 = [r8] ;; // M
add r8 = r11, r8 ;; // A
// first entry is jump pointer, second entry is gp
add r9 = 8, r8 ;; // A
// load jump pointer
ld8 r8 = [r8]
// load gp
ld8 gp = [r9] ;; // M
mov b6 = r8 ;; // I
// branch to target virtual function
br.call.sptk.few rp = b6 ;; // B
// epilog
mov ar.pfs = r37 // I
mov rp = r36 ;; // I
add sp = 0, r38 // A
add gp = 0, r39 // A
br.ret.sptk.few rp ;; // B
.endp
/* Magic indicating no need for an executable stack */
.section .note.GNU-stack, "", @progbits ; .previous