The Tor Browser / file revision

 # This Source Code Form is subject to the terms of the Mozilla Public

 # License, v. 2.0. If a copy of the MPL was not distributed with this

 # file, You can obtain one at http://mozilla.org/MPL/2.0/.

 .set r0,0; .set r1,1; .set r2,2; .set r3,3; .set r4,4

 .set r5,5; .set r6,6; .set r7,7; .set r8,8; .set r9,9

 .set r10,10; .set r11,11; .set r12,12; .set r13,13; .set r14,14

 .set r15,15; .set r16,16; .set r17,17; .set r18,18; .set r19,19

 .set r20,20; .set r21,21; .set r22,22; .set r23,23; .set r24,24

 .set r25,25; .set r26,26; .set r27,27; .set r28,28; .set r29,29

 .set r30,30; .set r31,31

 .set f0,0; .set f1,1; .set f2,2; .set f3,3; .set f4,4

 .set f5,5; .set f6,6; .set f7,7; .set f8,8; .set f9,9

 .set f10,10; .set f11,11; .set f12,12; .set f13,13; .set f14,14

 .set f15,15; .set f16,16; .set f17,17; .set f18,18; .set f19,19

 .set f20,20; .set f21,21; .set f22,22; .set f23,23; .set f24,24

 .set f25,25; .set f26,26; .set f27,27; .set f28,28; .set f29,29

 .set f30,30; .set f31,31

 # The ABI defines a fixed stack frame area of 4 doublewords (ELFv2)

 # or 6 doublewords (ELFv1); the last of these doublewords is used

 # as TOC pointer save area.  The fixed area is followed by a parameter

 # save area of 8 doublewords (used for vararg routines), followed

 # by space for parameters passed on the stack.

 #

 # We set STACK_TOC to the offset of the TOC pointer save area, and

 # STACK_PARAMS to the offset of the first on-stack parameter.

 #if _CALL_ELF == 2

 #define STACK_TOC      24

 #define STACK_PARAMS   96

 #else

 #define STACK_TOC      40

 #define STACK_PARAMS   112

 #endif

 #

 # NS_InvokeByIndex(nsISupports* that, uint32_t methodIndex,

 #                    uint32_t paramCount, nsXPTCVariant* params)

 #

 #if _CALL_ELF == 2

         .section ".text"

         .type   NS_InvokeByIndex,@function

         .globl  NS_InvokeByIndex

         .align 2

 NS_InvokeByIndex:

 0:      addis 2,12,(.TOC.-0b)@ha

         addi 2,2,(.TOC.-0b)@l

         .localentry NS_InvokeByIndex,.-NS_InvokeByIndex

 #else

         .section ".toc","aw"

         .section ".text"

         .align 2

         .globl  NS_InvokeByIndex

         .section ".opd","aw"

         .align 3

 NS_InvokeByIndex:

         .quad   .NS_InvokeByIndex,.TOC.@tocbase

         .previous

         .type   NS_InvokeByIndex,@function

 .NS_InvokeByIndex:

 #endif

         mflr    0

         std     0,16(r1)

         std     r29,-24(r1)

         std     r30,-16(r1)

         std     r31,-8(r1)

         mr      r29,r3                  # Save 'that' in r29

         mr      r30,r4                  # Save 'methodIndex' in r30

         mr      r31,r1                  # Save old frame

         # Allocate stack frame with space for params. Since at least the

         # first 7 parameters (not including 'that') will be in registers,

         # we don't actually need stack space for those. We must ensure

         # that the stack remains 16-byte aligned.

         #

         #  | (fixed area + |                | 7 GP | 13 FP | 3 NV |

         #  |  param. save) |(params)........| regs | regs  | regs |

         # (r1)......(+STACK_PARAMS)...  (-23*8).(-16*8).(-3*8)..(r31)

         # +stack frame, -unused stack params, +regs storage, +1 for alignment

         addi    r7,r5,((STACK_PARAMS/8)-7+7+13+3+1)

         rldicr  r7,r7,3,59              # multiply by 8 and mask with ~15

         neg     r7,r7

         stdux   r1,r1,r7

         # Call invoke_copy_to_stack(uint64_t* gpregs, double* fpregs,

         #                           uint32_t paramCount, nsXPTCVariant* s, 

         #                           uint64_t* d))

         # r5, r6 are passed through intact (paramCount, params)

         # r7 (d) has to be r1+STACK_PARAMS

         #        -- where parameters are passed on the stack.

         # r3, r4 are above that, easier to address from r31 than from r1

         subi    r3,r31,(23*8)           # r3 --> GPRS

         subi    r4,r31,(16*8)           # r4 --> FPRS

         addi    r7,r1,STACK_PARAMS      # r7 --> params

         bl      invoke_copy_to_stack

         nop

         # Set up to invoke function

         ld      r9,0(r29)               # vtable (r29 is 'that')

         mr      r3,r29                  # self is first arg, obviously

         sldi    r30,r30,3               # Find function descriptor 

         add     r9,r9,r30

         ld      r12,0(r9)

         std     r2,STACK_TOC(r1)        # Save r2 (TOC pointer)

 #if _CALL_ELF == 2

         mtctr   r12

 #else

         ld      r0,0(r12)               # Actual address from fd.

         mtctr   0

         ld      r11,16(r12)             # Environment pointer from fd.

         ld      r2,8(r12)               # TOC pointer from fd.

 #endif

         # Load FP and GP registers as required

         ld      r4, -(23*8)(r31) 

         ld      r5, -(22*8)(r31) 

         ld      r6, -(21*8)(r31) 

         ld      r7, -(20*8)(r31) 

         ld      r8, -(19*8)(r31) 

         ld      r9, -(18*8)(r31) 

         ld      r10, -(17*8)(r31) 

         lfd     f1, -(16*8)(r31)

         lfd     f2, -(15*8)(r31)

         lfd     f3, -(14*8)(r31)

         lfd     f4, -(13*8)(r31)

         lfd     f5, -(12*8)(r31)

         lfd     f6, -(11*8)(r31)

         lfd     f7, -(10*8)(r31)

         lfd     f8, -(9*8)(r31)

         lfd     f9, -(8*8)(r31)

         lfd     f10, -(7*8)(r31)

         lfd     f11, -(6*8)(r31)

         lfd     f12, -(5*8)(r31)

         lfd     f13, -(4*8)(r31)

         bctrl                           # Do it

         ld      r2,STACK_TOC(r1)        # Load our own TOC pointer

         ld      r1,0(r1)                # Revert stack frame

         ld      0,16(r1)                # Reload lr

         ld      29,-24(r1)              # Restore NVGPRS

         ld      30,-16(r1)

         ld      31,-8(r1)

         mtlr    0

         blr

 #if _CALL_ELF == 2

         .size   NS_InvokeByIndex,.-NS_InvokeByIndex

 #else

         .size   NS_InvokeByIndex,.-.NS_InvokeByIndex

 #endif

         # Magic indicating no need for an executable stack

         .section .note.GNU-stack, "", @progbits ; .previous