|
|
/***** Copyright (C) 1996-97 Intel Corporation. All rights reserved.****** The information and source code contained herein is the exclusive*** property of Intel Corporation and may not be disclosed, examined*** or reproduced in whole or in part without explicit written authorization*** from the company.**/
// TITLE("Context Conversion")//++// // Module Name://// convctx.s//// Abstract://// This module implements the code necessary to convert or assign // the user to kernel transition context to or from iA mode context.//// Author://// Edward G. Chron (echron) 01-Apr-1996//// Environment://// Kernel mode only.//// Revision History://////--
#include "ksia64.h"
.file "convctx.s" //++//// VOID// RtlEmFpToIaFpContext (// IN PCONTEXT ContextEM,// IN OUT UCHAR *iAFpArea // )//// Routine Description://// This function takes the values stored for the EM FP registers which// map the iA mode FP registers and copies them (in iA mode 10 byte// format) to the targeted 80 byte iA mode FP register context area.//// Arguments://// ContextEM (a0) - Pointer to the EM mode Context which contain the FP registers.// iAFpArea(a1) - Pointer to area to store 8 * 10 byte iA mode FP regs. //// Return Value://// None.//// N.B. The format iA mode FP registers is 80 bits and will not change.////--
LEAF_ENTRY(RtlEmFpToIaFpContext)
add t5 = -8, r0 // Need to convert 8 EM mode FP Regs cvtEmFp:
ldfe ft0 = [a0], 16 // Get EM FP reg mapping iA FP reg add t4 = -4, r0 // Need to store 2 bytes 4 times ;;
getf.sig t2 = ft0 // floating-point reg significand getf.exp t3 = ft0 // floating-point sign & exponent ;;
stIaFpReg:
st2 [a1] = t2, 2 // save 2 bytes of significand extr.u t2 = t2, 16, 48 // shift to the next two bytes adds t4 = 0x1, t4 // bump loop count ;;
cmp.lt p6, p0 = t4, r0 // done?(p6) br.cond.dpnt.few stIaFpReg // no, store the next two bytes adds t5 = 0x1, t5 // bump loop count add t4 = 0, t3 // copy of exponent and sign ;;
extr.u t4 = t4, 2, 62 // get the sign in bit 15 ;;
cmp.lt p6, p7 = t5, r0 // done? dep t3 = t3, t4, 0, 15 // just first 16 bits of exponent ;;
st2 [a1] = t3, 2 // save sign and iA exponent(p6) br.cond.dpnt.few cvtEmFp // no, process the next register(p7) br.ret.sptk brp ;;
LEAF_EXIT(RtlEmFpToIaFpContext)
//++//// VOID// RtlIaFpToEmFpContext (// IN UCHAR *iAFpArea, // IN OUT PCONTEXT ContextEM,// IN OUT FLOAT128 *FpWorkArea // )//// Routine Description://// This function takes the values stored for the EM FP registers which// map the iA mode FP registers and copies them (in iA mode 10 byte// format) to the targeted 80 byte iA mode FP register context area.//// Arguments://// ContextEM (a0) - Pointer to the EM mode Context registers that map iA mode FP regs.// iAFpArea(a1) - Pointer to area to store 8 * 10 byte iA mode FP regs. // alignedFp(a2) - FLOAT128 work area (aligned on 16 byte boundry).//// Return Value://// None.//// N.B. The format iA mode FP registers is 80 bits and will not change.////--
LEAF_ENTRY(RtlIaFpToEmFpContext) add t0 = 8, a0 // iA Fp Save Area Pointer add t5 = -8, r0 // Need to convert 8 iA mode FP Regs ;;
cvtIaFp: add t8 = -4, r0 // Need to load 2 bytes 4 times ld2 t3 = [t0], -2 // load exponent and sign ;;
add t4 = 0, t3 // copy of exponent and sign ;;
add t2 = 0, r0 extr.u t4 = t4, 15, 49 // get the sign in bit 17 ;;
dep t3 = t4, t3, 17, 1 // just first 16 bits of exponent
ldIaFpReg: ld2 t6 = [t0], -2 // load 2 bytes of significand adds t8 = 0x1, t8 // bump loop count ;;
or t2 = t2, t6 // retain until complete
cmp.lt p6, p0 = t8, r0 // done? ;;
(p6) dep.z t2 = t2, 16, 48 // no, shift to the next two bytes(p6) br.cond.dpnt.few ldIaFpReg // no, get next two bytes ;;
add t8 = -4, r0 // Need to store 2 bytes 4 times mov t7 = a2 // get address of aligned save area ;;
alignIaFp: st2 [t7] = t2, 2 // save 2 bytes of significand extr.u t2 = t2, 16, 48 // shift to the next two bytes adds t8 = 0x1, t8 // bump loop count ;;
cmp.lt p6, p0 = t8, r0 // done? add t6 = 0, t3 // copy of exponent and sign(p6) br.cond.dpnt.few alignIaFp // maybe ;;
nop.m 0 extr.u t6 = t6, 2, 62 // get the sign in bit 15 ;;
dep t3 = t3, t6, 0, 15 // just first 15 bits of exponent ;;
st2 [t7] = t3, 2 // save sign and iA exponent ldfe ft0 = [a2] adds t5 = 0x1, t5 // bump loop count ;;
stfe [a1] = ft0, CxFltT3 - CxFltT2 // Store value into EM FP Context cmp.lt p6, p7 = t5, r0 // done? ;;
(p6) add t2 = 0, r0 // no, reset significand for next
(p6) add t0 = 20, t0 // no, starting at the high end(p6) br.cond.dpnt.few cvtIaFp // no, get next context record(p7) br.ret.sptk brp ;;
LEAF_EXIT(RtlIaFpToEmFpContext)
|
