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;; Licensed to the .NET Foundation under one or more agreements.
;; The .NET Foundation licenses this file to you under the MIT license.
;; See the LICENSE file in the project root for more information.
#include "kxarm.h"
;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;; STUBS & DATA SECTIONS ;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;
THUNK_CODESIZE equ 0x10 ;; 4-byte mov, 2-byte add, 4-byte str, 4-byte ldr, 2-byte branch
THUNK_DATASIZE equ 0x08 ;; 2 dwords
THUNK_POOL_NUM_THUNKS_PER_PAGE equ 0xFA ;; 250 thunks per page
PAGE_SIZE equ 0x1000 ;; 4K
POINTER_SIZE equ 0x04
MACRO
NAMED_READONLY_DATA_SECTION $name, $areaAlias
AREA $areaAlias,DATA,READONLY
RO$name % 4
MEND
MACRO
NAMED_READWRITE_DATA_SECTION $name, $areaAlias
AREA $areaAlias,DATA
RW$name % 4
MEND
MACRO
LOAD_DATA_ADDRESS $groupIndex, $index
ALIGN 0x10 ;; make sure we align to 16-byte boundary for CFG table
;; set r12 to begining of data page : r12 <- pc - (THUNK_CODESIZE * current thunk's index - sizeof(mov+add instructions)) + PAGE_SIZE
;; fix offset of the data : r12 <- r12 + (THUNK_DATASIZE * current thunk's index)
mov.w r12, PAGE_SIZE + ($groupIndex * THUNK_DATASIZE * 10 + THUNK_DATASIZE * $index) - (8 + $groupIndex * THUNK_CODESIZE * 10 + THUNK_CODESIZE * $index)
add.n r12, r12, pc
MEND
MACRO
JUMP_TO_COMMON $groupIndex, $index
;; start : r12 points to the current thunks first data cell in the data page
;; put r12 into the red zone : r12 isn't changed
;; set r12 to begining of data page : r12 <- r12 - (THUNK_DATASIZE * current thunk's index)
;; fix offset to point to last DWROD in page : r12 <- r11 + PAGE_SIZE - POINTER_SIZE
;; jump to the location pointed at by the last dword in the data page
str.w r12, [sp, #-4]
ldr.w r12, [r12, #(PAGE_SIZE - POINTER_SIZE - ($groupIndex * THUNK_DATASIZE * 10 + THUNK_DATASIZE * $index))]
bx.n r12
MEND
MACRO
TenThunks $groupIndex
;; Each thunk will load the address of its corresponding data (from the page that immediately follows)
;; and call a common stub. The address of the common stub is setup by the caller (last dword
;; in the thunks data section) depending on the 'kind' of thunks needed (interop, fat function pointers, etc...)
;; Each data block used by a thunk consists of two dword values:
;; - Context: some value given to the thunk as context (passed in eax). Example for fat-fptrs: context = generic dictionary
;; - Target : target code that the thunk eventually jumps to.
LOAD_DATA_ADDRESS $groupIndex,0
JUMP_TO_COMMON $groupIndex,0
LOAD_DATA_ADDRESS $groupIndex,1
JUMP_TO_COMMON $groupIndex,1
LOAD_DATA_ADDRESS $groupIndex,2
JUMP_TO_COMMON $groupIndex,2
LOAD_DATA_ADDRESS $groupIndex,3
JUMP_TO_COMMON $groupIndex,3
LOAD_DATA_ADDRESS $groupIndex,4
JUMP_TO_COMMON $groupIndex,4
LOAD_DATA_ADDRESS $groupIndex,5
JUMP_TO_COMMON $groupIndex,5
LOAD_DATA_ADDRESS $groupIndex,6
JUMP_TO_COMMON $groupIndex,6
LOAD_DATA_ADDRESS $groupIndex,7
JUMP_TO_COMMON $groupIndex,7
LOAD_DATA_ADDRESS $groupIndex,8
JUMP_TO_COMMON $groupIndex,8
LOAD_DATA_ADDRESS $groupIndex,9
JUMP_TO_COMMON $groupIndex,9
MEND
MACRO
THUNKS_PAGE_BLOCK
TenThunks 0
TenThunks 1
TenThunks 2
TenThunks 3
TenThunks 4
TenThunks 5
TenThunks 6
TenThunks 7
TenThunks 8
TenThunks 9
TenThunks 10
TenThunks 11
TenThunks 12
TenThunks 13
TenThunks 14
TenThunks 15
TenThunks 16
TenThunks 17
TenThunks 18
TenThunks 19
TenThunks 20
TenThunks 21
TenThunks 22
TenThunks 23
TenThunks 24
MEND
;;
;; The first thunks section should be 64K aligned because it can get
;; mapped multiple times in memory, and mapping works on allocation
;; granularity boundaries (we don't want to map more than what we need)
;;
;; The easiest way to do so is by having the thunks section at the
;; first 64K aligned virtual address in the binary. We provide a section
;; layout file to the linker to tell it how to layout the thunks sections
;; that we care about. (ndp\rh\src\runtime\DLLs\app\mrt100_app_sectionlayout.txt)
;;
;; The PE spec says images cannot have gaps between sections (other
;; than what is required by the section alignment value in the header),
;; therefore we need a couple of padding data sections (otherwise the
;; OS will not load the image).
;;
NAMED_READONLY_DATA_SECTION PaddingFor64KAlignment0, "|.pad0|"
NAMED_READONLY_DATA_SECTION PaddingFor64KAlignment1, "|.pad1|"
NAMED_READONLY_DATA_SECTION PaddingFor64KAlignment2, "|.pad2|"
NAMED_READONLY_DATA_SECTION PaddingFor64KAlignment3, "|.pad3|"
NAMED_READONLY_DATA_SECTION PaddingFor64KAlignment4, "|.pad4|"
NAMED_READONLY_DATA_SECTION PaddingFor64KAlignment5, "|.pad5|"
NAMED_READONLY_DATA_SECTION PaddingFor64KAlignment6, "|.pad6|"
NAMED_READONLY_DATA_SECTION PaddingFor64KAlignment7, "|.pad7|"
NAMED_READONLY_DATA_SECTION PaddingFor64KAlignment8, "|.pad8|"
NAMED_READONLY_DATA_SECTION PaddingFor64KAlignment9, "|.pad9|"
NAMED_READONLY_DATA_SECTION PaddingFor64KAlignment10, "|.pad10|"
NAMED_READONLY_DATA_SECTION PaddingFor64KAlignment11, "|.pad11|"
NAMED_READONLY_DATA_SECTION PaddingFor64KAlignment12, "|.pad12|"
NAMED_READONLY_DATA_SECTION PaddingFor64KAlignment13, "|.pad13|"
NAMED_READONLY_DATA_SECTION PaddingFor64KAlignment14, "|.pad14|"
;;
;; Thunk Stubs
;; NOTE: Keep number of blocks in sync with macro/constant named 'NUM_THUNK_BLOCKS' in:
;; - ndp\FxCore\src\System.Private.CoreLib\System\Runtime\InteropServices\ThunkPool.cs
;; - ndp\rh\src\tools\rhbind\zapimage.h
;;
LEAF_ENTRY ThunkPool, "|.tks0|"
THUNKS_PAGE_BLOCK
LEAF_END ThunkPool
NAMED_READWRITE_DATA_SECTION ThunkData0, "|.tkd0|"
LEAF_ENTRY ThunkPool1, "|.tks1|"
THUNKS_PAGE_BLOCK
LEAF_END ThunkPool1
NAMED_READWRITE_DATA_SECTION ThunkData1, "|.tkd1|"
LEAF_ENTRY ThunkPool2, "|.tks2|"
THUNKS_PAGE_BLOCK
LEAF_END ThunkPool2
NAMED_READWRITE_DATA_SECTION ThunkData2, "|.tkd2|"
LEAF_ENTRY ThunkPool3, "|.tks3|"
THUNKS_PAGE_BLOCK
LEAF_END ThunkPool3
NAMED_READWRITE_DATA_SECTION ThunkData3, "|.tkd3|"
LEAF_ENTRY ThunkPool4, "|.tks4|"
THUNKS_PAGE_BLOCK
LEAF_END ThunkPool4
NAMED_READWRITE_DATA_SECTION ThunkData4, "|.tkd4|"
LEAF_ENTRY ThunkPool5, "|.tks5|"
THUNKS_PAGE_BLOCK
LEAF_END ThunkPool5
NAMED_READWRITE_DATA_SECTION ThunkData5, "|.tkd5|"
LEAF_ENTRY ThunkPool6, "|.tks6|"
THUNKS_PAGE_BLOCK
LEAF_END ThunkPool6
NAMED_READWRITE_DATA_SECTION ThunkData6, "|.tkd6|"
LEAF_ENTRY ThunkPool7, "|.tks7|"
THUNKS_PAGE_BLOCK
LEAF_END ThunkPool7
NAMED_READWRITE_DATA_SECTION ThunkData7, "|.tkd7|"
;;
;; IntPtr RhpGetThunksBase()
;;
LEAF_ENTRY RhpGetThunksBase
;; Return the address of the first thunk pool to the caller (this is really the base address)
ldr r0, =ThunkPool
sub r0, r0, #1
bx lr
LEAF_END RhpGetThunksBase
;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;; General Helpers ;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;
;;
;; int RhpGetNumThunksPerBlock()
;;
LEAF_ENTRY RhpGetNumThunksPerBlock
mov r0, THUNK_POOL_NUM_THUNKS_PER_PAGE
bx lr
LEAF_END RhpGetNumThunksPerBlock
;;
;; int RhpGetThunkSize()
;;
LEAF_ENTRY RhpGetThunkSize
mov r0, THUNK_CODESIZE
bx lr
LEAF_END RhpGetThunkSize
;;
;; int RhpGetNumThunkBlocksPerMapping()
;;
LEAF_ENTRY RhpGetNumThunkBlocksPerMapping
mov r0, 8
bx lr
LEAF_END RhpGetNumThunkBlocksPerMapping
;;
;; int RhpGetThunkBlockSize
;;
LEAF_ENTRY RhpGetThunkBlockSize
mov r0, PAGE_SIZE * 2
bx lr
LEAF_END RhpGetThunkBlockSize
;;
;; IntPtr RhpGetThunkDataBlockAddress(IntPtr thunkStubAddress)
;;
LEAF_ENTRY RhpGetThunkDataBlockAddress
mov r12, PAGE_SIZE - 1
bic r0, r0, r12
add r0, PAGE_SIZE
bx lr
LEAF_END RhpGetThunkDataBlockAddress
;;
;; IntPtr RhpGetThunkStubsBlockAddress(IntPtr thunkDataAddress)
;;
LEAF_ENTRY RhpGetThunkStubsBlockAddress
mov r12, PAGE_SIZE - 1
bic r0, r0, r12
sub r0, PAGE_SIZE
bx lr
LEAF_END RhpGetThunkStubsBlockAddress
END
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