forked from OSchip/llvm-project
ac2e25026f
If users tried to have a structure decl/init code like below
struct test_t t = { .memeber1 = 45 };
It is very likely that compiler will generate a readonly section
to hold up the init values for variable t. Later load of t members,
e.g., t.member1 will result in a read from readonly section.
BPF program cannot handle relocation. This will force users to
write:
struct test_t t = {};
t.member1 = 45;
This is just inconvenient and unintuitive.
This patch addresses this issue by implementing BPF PreprocessISelDAG.
For any load from a global constant structure or an global array of
constant struct, it attempts to
translate it into a constant directly. The traversal of the
constant struct and other constant data structures are similar
to where the assembler emits read-only sections.
Four different unit test cases are also added to cover
different scenarios.
Signed-off-by: Yonghong Song <yhs@fb.com>
llvm-svn: 305560
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| .. | ||
| alu8.ll | ||
| atomics.ll | ||
| basictest.ll | ||
| byval.ll | ||
| cc_args.ll | ||
| cc_args_be.ll | ||
| cc_ret.ll | ||
| cmp.ll | ||
| dwarfdump.ll | ||
| ex1.ll | ||
| fi_ri.ll | ||
| intrinsics.ll | ||
| lit.local.cfg | ||
| load.ll | ||
| loops.ll | ||
| many_args1.ll | ||
| many_args2.ll | ||
| mem_offset.ll | ||
| mem_offset_be.ll | ||
| objdump_atomics.ll | ||
| objdump_intrinsics.ll | ||
| objdump_trivial.ll | ||
| reloc.ll | ||
| rodata_1.ll | ||
| rodata_2.ll | ||
| rodata_3.ll | ||
| rodata_4.ll | ||
| sanity.ll | ||
| sdiv_error.ll | ||
| setcc.ll | ||
| shifts.ll | ||
| sockex2.ll | ||
| struct_ret1.ll | ||
| struct_ret2.ll | ||
| undef.ll | ||
| vararg1.ll | ||
| warn-call.ll | ||
| warn-stack.ll | ||