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author | Evan Cheng <evan.cheng@apple.com> | 2008-04-17 00:06:42 +0000 |
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committer | Evan Cheng <evan.cheng@apple.com> | 2008-04-17 00:06:42 +0000 |
commit | 621d157676940640f5d496a52b2936e37b81f1b4 (patch) | |
tree | f8f89b316efee00656b42ffa6c088526dd06373e /lib | |
parent | 4bf393a13e779d7a8eac3647df1781068a6dc732 (diff) | |
download | external_llvm-621d157676940640f5d496a52b2936e37b81f1b4.zip external_llvm-621d157676940640f5d496a52b2936e37b81f1b4.tar.gz external_llvm-621d157676940640f5d496a52b2936e37b81f1b4.tar.bz2 |
Fix a sub-register indice propagation bug.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@49832 91177308-0d34-0410-b5e6-96231b3b80d8
Diffstat (limited to 'lib')
-rw-r--r-- | lib/CodeGen/SimpleRegisterCoalescing.cpp | 19 |
1 files changed, 14 insertions, 5 deletions
diff --git a/lib/CodeGen/SimpleRegisterCoalescing.cpp b/lib/CodeGen/SimpleRegisterCoalescing.cpp index e9a5e25..a1f06a2 100644 --- a/lib/CodeGen/SimpleRegisterCoalescing.cpp +++ b/lib/CodeGen/SimpleRegisterCoalescing.cpp @@ -457,15 +457,14 @@ SimpleRegisterCoalescing::UpdateRegDefsUses(unsigned SrcReg, unsigned DstReg, MachineOperand &O = I.getOperand(); MachineInstr *UseMI = &*I; ++I; + unsigned OldSubIdx = O.getSubReg(); if (DstIsPhys) { - unsigned UseSubIdx = O.getSubReg(); unsigned UseDstReg = DstReg; - if (UseSubIdx) - UseDstReg = tri_->getSubReg(DstReg, UseSubIdx); + if (OldSubIdx) + UseDstReg = tri_->getSubReg(DstReg, OldSubIdx); O.setReg(UseDstReg); O.setSubReg(0); } else { - unsigned OldSubIdx = O.getSubReg(); // Sub-register indexes goes from small to large. e.g. // RAX: 0 -> AL, 1 -> AH, 2 -> AX, 3 -> EAX // EAX: 0 -> AL, 1 -> AH, 2 -> AX @@ -849,10 +848,20 @@ bool SimpleRegisterCoalescing::JoinCopy(CopyRec &TheCopy, bool &Again) { if (SrcIsPhys && isExtSubReg) { // r1024 = EXTRACT_SUBREG EAX, 0 then r1024 is really going to be // coalesced with AX. - SrcReg = tri_->getSubReg(SrcReg, SubIdx); + unsigned DstSubIdx = CopyMI->getOperand(0).getSubReg(); + assert(!DstSubIdx || DstSubIdx == SubIdx); + if (DstSubIdx != SubIdx) + // r1024<2> = EXTRACT_SUBREG EAX, 0. Then r1024 has already been + // coalesced to an INSERT_SUBREG so the subreg indices cancel out. + SrcReg = tri_->getSubReg(SrcReg, SubIdx); SubIdx = 0; } else if (DstIsPhys && isInsSubReg) { // EAX = INSERT_SUBREG EAX, r1024, 0 + unsigned SrcSubIdx = CopyMI->getOperand(2).getSubReg(); + assert(!SrcSubIdx || SrcSubIdx == SubIdx); + if (SrcSubIdx != SubIdx) + // EAX = INSERT_SUBREG EAX, r1024<2>, 0 Then r1024 has already been + // coalesced to an EXTRACT_SUBREG so the subreg indices cancel out. DstReg = tri_->getSubReg(DstReg, SubIdx); SubIdx = 0; } else if ((DstIsPhys && isExtSubReg) || (SrcIsPhys && isInsSubReg)) { |