[asan] fix debug info produced for asan-coverage=2

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@217106 91177308-0d34-0410-b5e6-96231b3b80d8
Don't treat 0 as a special value for int attributes.

Split the get() to not use a default value. This way
attributes can be added that have 0 as a legitimate value.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@217107 91177308-0d34-0410-b5e6-96231b3b80d8
R600/SI: Try to keep i32 mul on SALU

Also fix bug this exposed where when legalizing an immediate
operand, a v_mov_b32 would be created with a VSrc dest register.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@217108 91177308-0d34-0410-b5e6-96231b3b80d8