4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync// Contains low level routines for the Virtual Machine implementation
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync// on an Itanium-based platform.
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync// Copyright (c) 2006 - 2011, Intel Corporation. All rights reserved.<BR>
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync// This program and the accompanying materials
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync// are licensed and made available under the terms and conditions of the BSD License
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync// which accompanies this distribution. The full text of the license may be found at
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync// THE PROGRAM IS DISTRIBUTED UNDER THE BSD LICENSE ON AN "AS IS" BASIS,
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync// WITHOUT WARRANTIES OR REPRESENTATIONS OF ANY KIND, EITHER EXPRESS OR IMPLIED.
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync// Note: use of NESTED_SETUP requires number of locals (l) >= 3
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync//-----------------------------------------------------------------------------
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync// EbcAsmLLCALLEX
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync// Implements the low level EBC CALLEX instruction. Sets up the
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync// stack pointer, does the spill of function arguments, and
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync// calls the native function. On return it restores the original
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync// stack pointer and returns to the caller.
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync// Arguments :
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync// On Entry :
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync// in0 = Address of native code to call
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync// in1 = New stack pointer
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync// Return Value:
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync// As per static calling conventions.
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync//---------------------------------------------------------------------------
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync;// void EbcAsmLLCALLEX (UINTN FunctionAddr, UINTN EbcStackPointer)
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync // NESTED_SETUP uses loc0 and loc1 for context save
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync // Save a copy of the EBC VM stack pointer
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync // Copy stack arguments from EBC stack into registers.
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync // Assume worst case and copy 8.
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync // Save the original stack pointer
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync // Save the gp
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync // Set the new aligned stack pointer. Reserve space for the required
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync // 16-bytes of scratch area as well.
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync // Now call the function. Load up the function address from the descriptor
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync // pointed to by in0. Then get the gp from the descriptor at the following
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync // address in the descriptor.
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync // Restore the original stack pointer and gp
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync // Now return
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync//-----------------------------------------------------------------------------
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync// EbcLLCALLEXNative
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync// This function is called to execute an EBC CALLEX instruction.
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync// This instruction requires that we thunk out to external native
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync// code. On return, we restore the stack pointer to its original location.
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync// Destroys no working registers. For IPF, at least 8 register slots
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync// must be allocated on the stack frame to support any number of
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync// arguments beiung passed to the external native function. The
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync// size of the stack frame is FramePtr - EbcSp. If this size is less
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync// than 64-bytes, the amount of stack frame allocated is rounded up
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync// to 64-bytes
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync// Arguments On Entry :
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync// in0 = CallAddr The function address.
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync// in1 = EbcSp The new EBC stack pointer.
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync// in2 = FramePtr The frame pointer.
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync// Return Value:
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync// C Function Prototype:
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync// EbcLLCALLEXNative (
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync// IN UINTN CallAddr,
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync// IN UINTN EbcSp,
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync// IN VOID *FramePtr
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync//---------------------------------------------------------------------------
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync sub loc2 = loc2, loc3;; // loc2 = loc2 - loc3 = FramePtr - EbcSp
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync mov out2 = loc2;; // out2 = loc2 = FramePtr - EbcSp
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync cmp.leu p6 = out2, loc4;; // IF out2 < loc4 THEN P6=1 ELSE P6=0; IF (FramePtr - EbcSp) < 0x40 THEN P6 = 1 ELSE P6=0
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync (p6) mov loc2 = loc4;; // IF P6==1 THEN loc2 = loc4 = 0x40
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync sub r12 = r12, loc2;; // sp = sp - loc2 = sp - MAX (0x40, FramePtr - EbcSp)
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync and r12 = -0x10, r12 // Round sp down to the nearest 16-byte boundary
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync (p0) br.call.dptk.many b0 = CopyMem;; // CopyMem (sp, EbcSp, (FramePtr - EbcSp))
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync (p0) br.call.dptk.many b0 = EbcAsmLLCALLEX;; // EbcAsmLLCALLEX (CallAddr, sp)
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync// UINTN EbcLLGetEbcEntryPoint(VOID)
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync// Description:
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync// Simply return, so that the caller retrieves the return register
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync// contents (R8). That's where the thunk-to-ebc code stuffed the
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync// EBC entry point.