dG 5ht ,4/' der. 6.0.2.6551E|E $FDXDL(G Fl hFDH//faculty/best/faculty/best/crs/cs450/faculty/best/crs/cs550/lib/dlx-manual.ps/faculty/best/crs/cs550/lib/dlx-report.ps/faculty/best/Home.html/lib/pics/bu-logo.gif/~best/crs/cs550/yueh/dlxsim.htmlfridman/pdlx/report-pipe.htmlfridman/vdlx/report-vector.htmlgopher://gopher.bu.edu:70/11/Resources At Your Fingertips/School and College Bulletins/Undergraduate Programs 1994-95/College of Liberal Artsgopher://gopher.bu.edu:70/11/Resources At Your Fingertips/School and College Bulletins/Undergraduate Programs/College of Liberal Artshttp://cs-www.bu.edu/faculty/best/crs/cs101/Home.htmlhttp://cs-www.bu.edu/faculty/best/crs/cs550/fridman/pdlx/dlxsim.htmlhttp://cs-www.bu.edu/faculty/best/crs/cs550/fridman/vdlx/dlxsim.htmlhttp://cs-www.bu.edu/faculty/best/crs/cs550/Home.htmlhttp://cs-www.bu.edu/faculty/best/crs/cs550/yueh/dlxsim.htmlhttp://cs-www.bu.edu/faculty/best/Home.htmlhttp://cs-www.bu.edu/Home.htmlvti_version: S96/Home.html(S97/homeworks/01.Due=03-05.htmlh_S97/homeworks/03.Due=04-09.html S97/homeworks/01.Due=03-05.html S97/homeworks/02.Due=03-28.html,#S97/adm/getgrade.html S97/Home.html S97/Home.htmlyueh/dlxsim.html yueh/tomasulo-p1.html yueh/tomasulo-p2.html yueh/score.html yueh/tomasulo.html yueh/score-p1.html yueh/score-p2.html(S97/homeworks/03.Due=04-09.html(S97/homeworks/02.Due=03-28.htmlxmS97/homeworks/03.Due=04-09.html S97/homeworks/01.Due=03-05.html S97/Home.html S97/homeworks/02.Due=03-28.html fridman/pdlx/dlxsim.html S96/Home.htmlS97/homeworks/03.Due=04-09.html S94/Home.html S97/homeworks/01.Due=03-05.html S97/adm/getgrade.html S97/adm/references.html S97/Home.html S94/references.html S96/references.html S96/getgrade.html S96/Home.html S97/homeworks/02.Due=03-28.htmlLCS97/adm/getgrade.html S97/Home.html S96/getgrade.html S96/Home.html S96/Home.html fridman/vdlx/dlxsim.htmlS96/getgrade.html S96/Home.html S97/Home.html S97/adm/getgrade.htmlyueh/dlxsim.htmlxDCpP8DdE8DDCLFHDGH4>http://cs-www.bu.edu:80/http://web.bu.edu/http://web.bu.edu/CAShttp://web.bu.edu/pagetwo.htmlhttp://www.cs.bu.eduhttp://www.cs.bu.edu/faculty/best/crs/cs550http://www.cs.bu.edu/faculty/best/crs/cs550/fridman/vdlx/dlxsim.htmlhttp://www.cs.bu.edu/faculty/best/crs/cs550/yueh/dlxsim.htmlmailto:best@cs.bu.edumailto:cs550@cs.bu.edumailto:sadik@cs.bu.eduS94/yueh/dlxsim.htmlS96/homeworks/S96/lectures/S96/yueh/dlxsim.htmlS97/homeworks/S97/homeworks/web.bu.edu/CASvti_script:S97/homeworks/web.bu.eduvti_version:\m 1 Answer Home Page</TITLE> <H1>Scorehttp://cs-www.bu.edu/students/grads/patcai/yueh/Home.html addf f2,f0,f8 multf f4,f2,f2 multf f6,f2,f2 </CODE></PRE> At 5th clock cycle, only FU no.2 can read operands from register file. FU no.3 can't read operands because FU no.2 and no.3 share the same input line(see diagram of scoreboarding). FU no.3 has to stall one cycle to read the operands. In tomasulo's algorithm, the result broadcasts to all reservation stations by CDB. There is no stall in tomasulo's algorithm in this example.<BR> <PRE> SCOREBOARD 4 th clock cycle Instruction Issue Read opnds Exe complete Write Result +============================================================================+ addf f2,f0,f8 V V V multf f4,f2,f2 V multf f6,f2,f2 V nop V +============================================================================+ FU no. Name Busy Op Fi Fj Fk Qj Qk Rj Rk +=======================================================================+ 1 int YES nop YES YES 2 mul YES multf f4 f2 f2 4 4 NO NO 3 mul YES multf f6 f2 f2 4 4 NO NO 4 add YES addf f2 f0 f8 NO NO 5 add NO (null) 6 add NO (null) 7 div NO (null) +=====4'A  ==========================================================+ F0 F2 F4 F6 F8 F10 F12 F14 F16 F18 F20 F22 F24 F26 F28 F30 +-----------------------------------------------------------------------------+ FU 4 2 3 +=============================================================================+ (dlxsim) step stopped after single step, pc = _main+0x10: nop (dlxsim) stats score SCOREBOARD 5 th clock cycle Instruction Issue Read opnds Exe complete Write Res S96/Home.html@5S97/adm/getgrade.html S96/getgrade.html S96/Home.html S97/adm/getgrade.html S97/adm/references.htmlyueh/dlxsim.html S96/Home.htmlS94/references.html(S96/getgrade.html S96/Home.htmlxmS97/homeworks/03.Due=04-09.html S97/homeworks/01.Due=03-05.html S97/Home.html S97/homeworks/02.Due=03-28.html S97/Home.html S97/Home.htmlxmS97/homeworks/03.Due=04-09.html S97/homeworks/01.Due=03-05.html S97/Home.html S97/homeworks/02.Due=03-28.html S96/Home.html(S97/homeworks/01.Due=03-05.htmlS96/references.htmlyueh/dlxsim.html yueh/tomasulo-p1.html yueh/tomasulo-p2.html yueh/score.html fridman/pdlx/dlxsim.html yueh/tomasulo.html yueh/score-p1.html yueh/score-p2.html fridman/vdlx/dlxsim.htmlS96/getgrade.html$s97/homeworks/web.bu.edu/cas