COFF section flags are not idempotent:
'rd' will make a read-write section because 'd' implies write
'dr' will make a read-only section because 'r' disables write
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@228490 91177308-0d34-0410-b5e6-96231b3b80d8
The constant pool entry code for WinCOFF assumed that vector constants
would be formed using ConstantDataVector, it did not expect to see a
ConstantVector. Furthermore, it did not expect undef as one of the
elements of the vector.
ConstantVectors should be handled like ConstantDataVectors, treat Undef
as zero.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@213038 91177308-0d34-0410-b5e6-96231b3b80d8
COFF lacks a feature that other object file formats support: mergeable
sections.
To work around this, MSVC sticks constant pool entries in special COMDAT
sections so that each constant is in it's own section. This permits
unused constants to be dropped and it also allows duplicate constants in
different translation units to get merged together.
This fixes PR20262.
Differential Revision: http://reviews.llvm.org/D4482
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@213006 91177308-0d34-0410-b5e6-96231b3b80d8
