MFC r356329:
Merge commit 41449c58c from llvm git (by Roger Ferrer Ibanez):
[RISCV] Fix evaluation of %pcrel_lo
The following testcase
function:
.Lpcrel_label1:
auipc a0, %pcrel_hi(other_function)
addi a1, a0, %pcrel_lo(.Lpcrel_label1)
.p2align 2 # Causes a new fragment to be emitted
.type other_function,@function
other_function:
ret
exposes an odd behaviour in which only the %pcrel_hi relocation is
evaluated but not the %pcrel_lo.
$ llvm-mc -triple riscv64 -filetype obj t.s | llvm-objdump -d -r -
<stdin>: file format ELF64-riscv
Disassembly of section .text:
0000000000000000 function:
0: 17 05 00 00 auipc a0, 0
4: 93 05 05 00 mv a1, a0
0000000000000004: R_RISCV_PCREL_LO12_I other_function+4
0000000000000008 other_function:
8: 67 80 00 00 ret
The reason seems to be that in RISCVAsmBackend::shouldForceRelocation
we only consider the fragment but in RISCVMCExpr::evaluatePCRelLo we
consider the section. This usually works but there are cases where
the section may still be the same but the fragment may be another
one. In that case we end forcing a %pcrel_lo relocation without any
%pcrel_hi.
This patch makes RISCVAsmBackend::shouldForceRelocation use the
section, if any, to determine if the relocation must be forced or
not.
Differential Revision: https://reviews.llvm.org/D60657This is a prerequisite for building and linking hard- and soft-float
riscv worlds with clang and lld.
Requested by: jhb
MFC r356330:
Merge commit da7b129b1 from llvm git (by James Clarke):
[RISCV] Don't force Local Exec TLS for non-PIC Summary: Forcing Local Exec TLS requires the use of copy relocations. Copy relocations need special handling in the runtime linker when being used against TLS symbols, which is present in glibc, but not in FreeBSD nor musl, and so cannot be relied upon. Moreover, copy relocations are a hack that embed the size of an object in the ABI when it otherwise wouldn't be, and break protected symbols (which are expected to be DSO local), whilst also wasting space, thus they should be avoided whenever possible. As discussed in D70398, RISC-V should move away from forcing Local Exec, and instead use Initial Exec like other targets, with possible linker relaxation to follow. The RISC-V GCC maintainers also intend to adopt this more-conventional behaviour (see https://github.com/riscv/riscv-elf-psabi-doc/issues/122). Reviewers: asb, MaskRay Reviewed By: MaskRay Subscribers: emaste, krytarowski, hiraditya, rbar, johnrusso, simoncook, sabuasal, niosHD, kito-cheng, shiva0217, zzheng, edward-jones, rogfer01, MartinMosbeck, brucehoult, the_o, rkruppe, PkmX, jocewei, psnobl, benna, Jim, lenary, s.egerton, pzheng, sameer.abuasal, apazos, llvm-commits, bsdjhb Tags: #llvm Differential Revision: https://reviews.llvm.org/D70649
This is a prerequisite for building and linking hard- and soft-float
riscv worlds with clang and lld.
Requested by: jhb
MFC r356331:
Merge commit c6b09bff5 from llvm git (by Luís Marques):
[RISCV] Fix wrong CFI directives Summary: Removes CFI CFA directives that could incorrectly propagate beyond the basic block they were inteded for. Specifically it removes the epilogue CFI directives. See the branch_and_tail_call test for an example of the issue. Should fix the stack unwinding issues caused by the incorrect directives. Reviewers: asb, lenary, shiva0217 Reviewed By: lenary Tags: #llvm Differential Revision: https://reviews.llvm.org/D69723
This is a prerequisite for building and linking hard- and soft-float
riscv worlds with clang and lld.
Requested by: jhb
MFC r356332:
Merge commit d7be3eab5 from llvm git (by Luís Marques):
[RISCV] Handle fcopysign(f32, f64) and fcopysign(f64, f32) Summary: Adds tablegen patterns to explicitly handle fcopysign where the magnitude and sign arguments have different types, due to the sign value casts being removed the by DAGCombiner. Support for RV32IF follows in a separate commit. Adds tests for all relevant scenarios except RV32IF. Reviewers: lenary Reviewed By: lenary Tags: #llvm Differential Revision: https://reviews.llvm.org/D70678
This is a prerequisite for building and linking hard- and soft-float
riscv worlds with clang and lld.
Requested by: jhb
MFC r356333:
Merge commit 189b7393d from llvm git (by John Baldwin):
[lld][RISCV] Use an e_flags of 0 if there are only binary input files. Summary: If none of the input files are ELF object files (for example, when generating an object file from a single binary input file via "-b binary"), use a fallback value for the ELF header flags instead of crashing with an assertion failure. Reviewers: MaskRay, ruiu, espindola Reviewed By: MaskRay, ruiu Subscribers: kevans, grimar, emaste, arichardson, asb, rbar, johnrusso, simoncook, sabuasal, niosHD, kito-cheng, shiva0217, zzheng, edward-jones, rogfer01, MartinMosbeck, brucehoult, the_o, rkruppe, PkmX, jocewei, psnobl, benna, Jim, lenary, s.egerton, pzheng, sameer.abuasal, apazos, luismarques, llvm-commits, jrtc27 Tags: #llvm Differential Revision: https://reviews.llvm.org/D71101
This is a prerequisite for building and linking hard- and soft-float
riscv worlds with clang and lld.
Requested by: jhb