When -fgpu-rdc is used for linking relocatable objects, clang driver launches
clang-offload-bundler to extract a device relocatable object from each input
relocatable object file and passes the extracted files to lld. The input relocatable
object file could either come from HIP program or C++ program. The relocatable
object file from C++ program does not contain device relocatable objects, therefore
clang-offload-bundler extracts an empty file and passes it to lld. lld treates
empty file as linker script. When there is no object input file to lld, lld
will emit error:
target emulation unknown: -m or at least one .o file required
This patch adds "elf64_amdgpu" to lld so that lld always know the target
no matter whether there are object input files or not.
Reviewed by: Artem Belevich, Fangrui Song
Differential Revision: https://reviews.llvm.org/D138221
Previously, we linked in the ROCm device libraries which provide math
and other utility functions late. This is not stricly correct as this
library contains several flags that are only set per-TU, such as fast
math or denormalization. This patch changes this to pass the bitcode
libraries per-TU using the same method we use for the CUDA libraries.
This has the advantage that we correctly propagate attributes making
this implementation more correct. Additionally, many annoying unused
functions were not being fully removed during LTO. This lead to
erroneous warning messages and remarks on unused functions.
I am not sure if not finding these libraries should be a hard error. let
me know if it should be demoted to a warning saying that some device
utilities will not work without them.
Reviewed By: JonChesterfield
Differential Revision: https://reviews.llvm.org/D133726
Fix a typo about -fno-gpu-sanitize handling and disable warnings when
-fno-gpu-sanitize is specified.
Reviewed by: Artem Belevich
Differential Revision: https://reviews.llvm.org/D121302
HIP programs compiled with -c -fgpu-rdc generate clang-offload-bundler
bundles which contain bitcode for different GPU's.
Such files can be archived to an archive file which can be linked with
HIP programs with -fgpu-rdc.
This patch adds suppor of linking archive of bundled bitcode.
When an archive of bundled bitcode is passed to clang by -l, for each
GPU specified through --offload-arch, clang extracts bitcode from
the archive and creates a new archive for that GPU and pass it
to lld.
Reviewed by: Artem Belevich
Differential Revision: https://reviews.llvm.org/D120070
Fixes: SWDEV-321741, SWDEV-315773
This patch refactors the HIP tool chain for new HIP tool chain, HIPSPV
tool chain, which is added in the follow up patch part 2.
Rename HIPToolChain to HIPAMDToolChain and Renames HIP.* files to HIPAMD.*.
Introduce HIPUtility.* file where common HIP utilities, shared among HIP
tool chain implementations, are placed in.
Move constructHIPFatbinCommand() and
constructGenerateObjFileFromHIPFatBinary() to HIPUtility. HIPSPV tool
chain is going to use them.
Tweak bundle target ID in constructHIPFatbinCommand(): extra dashes are
dropped if the Target ID is empty and 'hip' offload kind is made default
for non-AMD targets.
Patch by: Henry Linjamäki
Reviewed by: Yaxun Liu, Artem Belevich, Eric Christopher
Differential Revision: https://reviews.llvm.org/D110549
Yaxun (Sam) Liu