<HTML><BODY style="word-wrap: break-word; -khtml-nbsp-mode: space; -khtml-line-break: after-white-space; "><BR><DIV><DIV>On Aug 9, 2007, at 3:20 PM, Evan Cheng wrote:</DIV><BR class="Apple-interchange-newline"><BLOCKQUOTE type="cite"> <BR><DIV><DIV>On Aug 9, 2007, at 2:45 PM, Christopher Lamb wrote:</DIV><BR class="Apple-interchange-newline"><BLOCKQUOTE type="cite"><DIV style="word-wrap: break-word; -khtml-nbsp-mode: space; -khtml-line-break: after-white-space; ">Evan,<DIV><BR class="khtml-block-placeholder"></DIV><DIV>I don't think that this change is working quite correctly, and may not be needed, given the way that the subreg code uses those values. This is currently causing regressions in dejagnu.</DIV><DIV><BR class="khtml-block-placeholder"></DIV><DIV>The register classes in the SubRegClassList are used when new subreg vregs are created. The key is that the register class be valid for the register-register mappings in the SubRegSet of the corresponding index, that is that the all the subregs of the class must be members of the SubRegClass, not that the sets must be equal.</DIV><DIV><BR class="khtml-block-placeholder"></DIV><DIV>Every subreg of GR16_ is a member of GR8, and every subreg of GR32_ is properly a member of GR8 or GR16.</DIV></DIV></BLOCKQUOTE><DIV>Hi Chris,</DIV><DIV><BR class="webkit-block-placeholder"></DIV>Sorry, I am not following. Given GR16_ contains only AX, CX, DX, and BX. How can its subregister class contains GR8 (which includes register like R8B, SIL) that have no relationship with AX, etc.</DIV></BLOCKQUOTE><DIV><BR class="khtml-block-placeholder"></DIV><DIV>GR16_ contains only [AX, CX, DX, BX], this means that only valid SubRegSets (1) are [AL, CL, DL, BL] which are all members of GR8. Constraining the superreg to GR16_ is necessary, but constraining the subreg in a new class other than GR8 is not.</DIV><BR><BLOCKQUOTE type="cite"><DIV>I am ok with backing out the patch for now. But something else seems wrong.</DIV></BLOCKQUOTE><DIV><BR class="khtml-block-placeholder"></DIV><DIV>EXTRACT_SUBREG needs to know what register class to use to create new vregs during ScheduleDAG. If the register class that EXTRACT_SUBREG produces doesn't match the input register class of the consuming instruction then you get the errors that your patch created. You have EXTRACT_SUBREG producing GR8_ vregs and target instructions expecting to use a GR8. To get around this you could have a MOVGR#_toGR# instruction placed after every use of EXTRACT_SUBREG, but that'd be moving from a subclass to a superclass which can always be eliminated (i.e MOV GR8_ -> GR8 is not necessary because all of GR8_ are already in GR8).</DIV><DIV><BR class="khtml-block-placeholder"></DIV><DIV>Hope that helps explain it.</DIV><DIV><BR class="khtml-block-placeholder"></DIV><DIV>--</DIV><DIV>Chris</DIV><BR><BLOCKQUOTE type="cite"><DIV><BLOCKQUOTE type="cite"><DIV style="word-wrap: break-word; -khtml-nbsp-mode: space; -khtml-line-break: after-white-space; "><DIV><DIV><DIV>On Aug 9, 2007, at 11:05 AM, Evan Cheng wrote:</DIV><BR class="Apple-interchange-newline"><BLOCKQUOTE type="cite"><DIV style="margin-top: 0px; margin-right: 0px; margin-bottom: 0px; margin-left: 0px; ">Author: evancheng</DIV><DIV style="margin-top: 0px; margin-right: 0px; margin-bottom: 0px; margin-left: 0px; ">Date: Thu Aug<SPAN class="Apple-converted-space"> </SPAN>9 13:05:17 2007</DIV><DIV style="margin-top: 0px; margin-right: 0px; margin-bottom: 0px; margin-left: 0px; ">New Revision: 40970</DIV><DIV style="margin-top: 0px; margin-right: 0px; margin-bottom: 0px; margin-left: 0px; min-height: 14px; "><BR></DIV><DIV style="margin-top: 0px; margin-right: 0px; margin-bottom: 0px; margin-left: 0px; ">URL: <A href="http://llvm.org/viewvc/llvm-project?rev=40970&view=rev">http://llvm.org/viewvc/llvm-project?rev=40970&view=rev</A></DIV><DIV style="margin-top: 0px; margin-right: 0px; margin-bottom: 0px; margin-left: 0px; ">Log:</DIV><DIV style="margin-top: 0px; margin-right: 0px; margin-bottom: 0px; margin-left: 0px; ">GR16_ sub-register class should be GR8_, not GR8. That is, it should only be 8-bit registers in 32-bit mode. Ditto for GR32_.</DIV><DIV style="margin-top: 0px; margin-right: 0px; margin-bottom: 0px; margin-left: 0px; min-height: 14px; "><BR></DIV><DIV style="margin-top: 0px; margin-right: 0px; margin-bottom: 0px; margin-left: 0px; ">Modified:</DIV><DIV style="margin-top: 0px; margin-right: 0px; margin-bottom: 0px; margin-left: 0px; "><SPAN class="Apple-converted-space"> </SPAN>llvm/trunk/lib/Target/X86/X86RegisterInfo.td</DIV><DIV style="margin-top: 0px; margin-right: 0px; margin-bottom: 0px; margin-left: 0px; min-height: 14px; "><BR></DIV><DIV style="margin-top: 0px; margin-right: 0px; margin-bottom: 0px; margin-left: 0px; ">Modified: llvm/trunk/lib/Target/X86/X86RegisterInfo.td</DIV><DIV style="margin-top: 0px; margin-right: 0px; margin-bottom: 0px; margin-left: 0px; ">URL: <A href="http://llvm.org/viewvc/llvm-project/llvm/trunk/lib/Target/X86/X86RegisterInfo.td?rev=40970&r1=40969&r2=40970&view=diff">http://llvm.org/viewvc/llvm-project/llvm/trunk/lib/Target/X86/X86RegisterInfo.td?rev=40970&r1=40969&r2=40970&view=diff</A></DIV><DIV style="margin-top: 0px; margin-right: 0px; margin-bottom: 0px; margin-left: 0px; min-height: 14px; "><BR></DIV><DIV style="margin-top: 0px; margin-right: 0px; margin-bottom: 0px; margin-left: 0px; ">==============================================================================</DIV><DIV style="margin-top: 0px; margin-right: 0px; margin-bottom: 0px; margin-left: 0px; ">--- llvm/trunk/lib/Target/X86/X86RegisterInfo.td (original)</DIV><DIV style="margin-top: 0px; margin-right: 0px; margin-bottom: 0px; margin-left: 0px; ">+++ llvm/trunk/lib/Target/X86/X86RegisterInfo.td Thu Aug<SPAN class="Apple-converted-space"> </SPAN>9 13:05:17 2007</DIV><DIV style="margin-top: 0px; margin-right: 0px; margin-bottom: 0px; margin-left: 0px; ">@@ -417,13 +417,14 @@</DIV><DIV style="margin-top: 0px; margin-right: 0px; margin-bottom: 0px; margin-left: 0px; "><SPAN class="Apple-converted-space"> </SPAN>}</DIV><DIV style="margin-top: 0px; margin-right: 0px; margin-bottom: 0px; margin-left: 0px; min-height: 14px; "><BR></DIV><DIV style="margin-top: 0px; margin-right: 0px; margin-bottom: 0px; margin-left: 0px; min-height: 14px; "><BR></DIV><DIV style="margin-top: 0px; margin-right: 0px; margin-bottom: 0px; margin-left: 0px; ">-// GR16, GR32 subclasses which contain registers that have R8 sub-registers.</DIV><DIV style="margin-top: 0px; margin-right: 0px; margin-bottom: 0px; margin-left: 0px; ">+// GR16, GR32 subclasses which contain registers that have GR8 sub-registers.</DIV><DIV style="margin-top: 0px; margin-right: 0px; margin-bottom: 0px; margin-left: 0px; "><SPAN class="Apple-converted-space"> </SPAN>// These should only be used for 32-bit mode.</DIV><DIV style="margin-top: 0px; margin-right: 0px; margin-bottom: 0px; margin-left: 0px; ">+def GR8_ : RegisterClass<"X86", [i8], 8, [AL, CL, DL, BL, AH, CH, DH, BH]>;</DIV><DIV style="margin-top: 0px; margin-right: 0px; margin-bottom: 0px; margin-left: 0px; "><SPAN class="Apple-converted-space"> </SPAN>def GR16_ : RegisterClass<"X86", [i16], 16, [AX, CX, DX, BX]> {</DIV><DIV style="margin-top: 0px; margin-right: 0px; margin-bottom: 0px; margin-left: 0px; ">-<SPAN class="Apple-converted-space"> </SPAN>let SubRegClassList = [GR8];</DIV><DIV style="margin-top: 0px; margin-right: 0px; margin-bottom: 0px; margin-left: 0px; ">+<SPAN class="Apple-converted-space"> </SPAN>let SubRegClassList = [GR8_];</DIV><DIV style="margin-top: 0px; margin-right: 0px; margin-bottom: 0px; margin-left: 0px; "><SPAN class="Apple-converted-space"> </SPAN>}</DIV><DIV style="margin-top: 0px; margin-right: 0px; margin-bottom: 0px; margin-left: 0px; "><SPAN class="Apple-converted-space"> </SPAN>def GR32_ : RegisterClass<"X86", [i32], 32, [EAX, ECX, EDX, EBX]> {</DIV><DIV style="margin-top: 0px; margin-right: 0px; margin-bottom: 0px; margin-left: 0px; ">-<SPAN class="Apple-converted-space"> </SPAN>let SubRegClassList = [GR8, GR16];</DIV><DIV style="margin-top: 0px; margin-right: 0px; margin-bottom: 0px; margin-left: 0px; ">+<SPAN class="Apple-converted-space"> </SPAN>let SubRegClassList = [GR8_, GR16_];</DIV><DIV style="margin-top: 0px; margin-right: 0px; margin-bottom: 0px; margin-left: 0px; "><SPAN class="Apple-converted-space"> </SPAN>}</DIV><DIV style="margin-top: 0px; margin-right: 0px; margin-bottom: 0px; margin-left: 0px; min-height: 14px; "><BR></DIV><DIV style="margin-top: 0px; margin-right: 0px; margin-bottom: 0px; margin-left: 0px; "><SPAN class="Apple-converted-space"> </SPAN>// Scalar SSE2 floating point registers.</DIV><DIV style="margin-top: 0px; margin-right: 0px; margin-bottom: 0px; margin-left: 0px; min-height: 14px; "><BR></DIV><DIV style="margin-top: 0px; margin-right: 0px; margin-bottom: 0px; margin-left: 0px; min-height: 14px; "><BR></DIV><DIV style="margin-top: 0px; margin-right: 0px; margin-bottom: 0px; margin-left: 0px; ">_______________________________________________</DIV><DIV style="margin-top: 0px; margin-right: 0px; margin-bottom: 0px; margin-left: 0px; ">llvm-commits mailing list</DIV><DIV style="margin-top: 0px; margin-right: 0px; margin-bottom: 0px; margin-left: 0px; "><A href="mailto:llvm-commits@cs.uiuc.edu">llvm-commits@cs.uiuc.edu</A></DIV><DIV style="margin-top: 0px; margin-right: 0px; margin-bottom: 0px; margin-left: 0px; "><A href="http://lists.cs.uiuc.edu/mailman/listinfo/llvm-commits">http://lists.cs.uiuc.edu/mailman/listinfo/llvm-commits</A></DIV> </BLOCKQUOTE></DIV><BR><DIV> <SPAN class="Apple-style-span" style="border-collapse: separate; border-spacing: 0px 0px; color: rgb(0, 0, 0); font-family: Helvetica; font-size: 12px; font-style: normal; font-variant: normal; font-weight: normal; letter-spacing: normal; line-height: normal; text-align: auto; -khtml-text-decorations-in-effect: none; text-indent: 0px; -apple-text-size-adjust: auto; text-transform: none; orphans: 2; white-space: normal; widows: 2; word-spacing: 0px; "><SPAN class="Apple-style-span" style="border-collapse: separate; border-spacing: 0px 0px; color: rgb(0, 0, 0); font-family: Helvetica; font-size: 12px; font-style: normal; font-variant: normal; font-weight: normal; letter-spacing: normal; line-height: normal; text-align: auto; -khtml-text-decorations-in-effect: none; text-indent: 0px; -apple-text-size-adjust: auto; text-transform: none; orphans: 2; white-space: normal; widows: 2; word-spacing: 0px; "><DIV>--</DIV><DIV>Christopher Lamb</DIV><DIV><BR class="khtml-block-placeholder"></DIV><BR class="Apple-interchange-newline"></SPAN></SPAN> </DIV><BR></DIV></DIV>_______________________________________________<BR>llvm-commits mailing list<BR><A href="mailto:llvm-commits@cs.uiuc.edu">llvm-commits@cs.uiuc.edu</A><BR><A href="http://lists.cs.uiuc.edu/mailman/listinfo/llvm-commits">http://lists.cs.uiuc.edu/mailman/listinfo/llvm-commits</A><BR></BLOCKQUOTE></DIV><BR><DIV style="margin-top: 0px; margin-right: 0px; margin-bottom: 0px; margin-left: 0px; ">_______________________________________________</DIV><DIV style="margin-top: 0px; margin-right: 0px; margin-bottom: 0px; margin-left: 0px; ">llvm-commits mailing list</DIV><DIV style="margin-top: 0px; margin-right: 0px; margin-bottom: 0px; margin-left: 0px; "><A href="mailto:llvm-commits@cs.uiuc.edu">llvm-commits@cs.uiuc.edu</A></DIV><DIV style="margin-top: 0px; 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