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| author | Akira Hatanaka <ahatanaka@mips.com> | 2013-05-16 19:48:37 +0000 |
|---|---|---|
| committer | Akira Hatanaka <ahatanaka@mips.com> | 2013-05-16 19:48:37 +0000 |
| commit | ec4db6ab5f64318b1aa2351f7e710569869193e9 (patch) | |
| tree | be4c14d2e226a3fb22433a0b012f0f38d25f804b /docs/ProgrammersManual.rst | |
| parent | 50f02f9d21f3d3558249910b4e05abb49e8c6f50 (diff) | |
| download | external_llvm-ec4db6ab5f64318b1aa2351f7e710569869193e9.zip external_llvm-ec4db6ab5f64318b1aa2351f7e710569869193e9.tar.gz external_llvm-ec4db6ab5f64318b1aa2351f7e710569869193e9.tar.bz2 | |
[mips] Fix instruction selection pattern for sint_to_fp node to avoid emitting an
invalid instruction sequence.
Rather than emitting an int-to-FP move instruction and an int-to-FP conversion
instruction during instruction selection, we emit a pseudo instruction which gets
expanded post-RA. Without this change, register allocation can possibly insert a
floating point register move instruction between the two instructions, which is not
valid according to the ISA manual.
mtc1 $f4, $4 # int-to-fp move instruction.
mov.s $f2, $f4 # move contents of $f4 to $f2.
cvt.s.w $f0, $f2 # int-to-fp conversion.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@182042 91177308-0d34-0410-b5e6-96231b3b80d8
Diffstat (limited to 'docs/ProgrammersManual.rst')
0 files changed, 0 insertions, 0 deletions