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author | Bill Wendling <isanbard@gmail.com> | 2010-06-09 19:00:55 +0000 |
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committer | Bill Wendling <isanbard@gmail.com> | 2010-06-09 19:00:55 +0000 |
commit | d64ba3ee62cc854218d9b76b9420493d82313d06 (patch) | |
tree | 98142a3c2b72e7d6a92983a7994436c21fa323f5 /lib/CodeGen/TwoAddressInstructionPass.cpp | |
parent | 1d451dff63e9c4241794a3645dfe4ee67efe5b22 (diff) |
It's an error to translate this:
%reg1025 = <sext> %reg1024
...
%reg1026 = SUBREG_TO_REG 0, %reg1024, 4
into this:
%reg1025 = <sext> %reg1024
...
%reg1027 = EXTRACT_SUBREG %reg1025, 4
%reg1026 = SUBREG_TO_REG 0, %reg1027, 4
The problem here is that SUBREG_TO_REG is there to assert that an implicit zext
occurs. It doesn't insert a zext instruction. If we allow the EXTRACT_SUBREG
here, it will give us the value after the <sext>, not the original value of
%reg1024 before <sext>.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@105741 91177308-0d34-0410-b5e6-96231b3b80d8
Diffstat (limited to 'lib/CodeGen/TwoAddressInstructionPass.cpp')
0 files changed, 0 insertions, 0 deletions