Hi all,
I have instrumented a function call like foo(&a,&b) into the gimple SSA
representation (gcc-4.5) and the consequent optimizations can not pass
my instrumented code. The back traces are as followings. The error
occurred when the pass dse tried to test if the call I inserted may use
a memory reference. It is because the arguments &a is not a SSA_VAR or
INDIRECT_REF, so the assert in function
bool
refs_may_alias_p_1 (ao_ref *ref1, ao_ref *ref2, bool tbaa_p)
gcc_assert ((!ref1->ref
|| SSA_VAR_P (ref1->ref)
|| handled_component_p (ref1->ref)
|| INDIRECT_REF_P (ref1->ref)
|| TREE_CODE (ref1->ref) == TARGET_MEM_REF
|| TREE_CODE (ref1->ref) == CONST_DECL)
&& (!ref2->ref
|| SSA_VAR_P (ref2->ref)
|| handled_component_p (ref2->ref)
|| INDIRECT_REF_P (ref2->ref)
|| TREE_CODE (ref2->ref) == TARGET_MEM_REF
|| TREE_CODE (ref2->ref) == CONST_DECL));
was violated.
Does anyone know why the function arguments must be a SSA_VAR or
INDIRECT_REF here? Have I missed to perform any actions to maintain the
consistency of Gimple SSA?
#0 0x00007ffff6fc8ee0 in exit () from /lib/libc.so.6
#1 0x00000000005ae4ce in diagnostic_action_after_output
(context=0x1323880, diagnostic=0x7fffffffd870) at
../../src/gcc/diagnostic.c:198
#2 0x00000000005aed54 in diagnostic_report_diagnostic
(context=0x1323880, diagnostic=0x7fffffffd870) at
../../src/gcc/diagnostic.c:424
#3 0x00000000005afdc3 in internal_error (gmsgid=0xddfb57 "in %s, at
%s:%d") at ../../src/gcc/diagnostic.c:709
#4 0x00000000005aff4f in fancy_abort (file=0xe42670
"../../src/gcc/tree-ssa-alias.c", line=786, function=0xe427e0
"refs_may_alias_p_1")
at ../../src/gcc/diagnostic.c:763
#5 0x00000000008a1adb in refs_may_alias_p_1 (ref1=0x7fffffffdab0,
ref2=0x7fffffffdb50, tbaa_p=1 '\001')
at ../../src/gcc/tree-ssa-alias.c:775
#6 0x00000000008a2b12 in ref_maybe_used_by_call_p_1
(call=0x7ffff6790630, ref=0x7fffffffdb50) at
../../src/gcc/tree-ssa-alias.c:1133
#7 0x00000000008a2d2e in ref_maybe_used_by_call_p (call=0x7ffff6790630,
ref=0x7ffff6848048) at ../../src/gcc/tree-ssa-alias.c:1147
#8 0x00000000008a2dfa in ref_maybe_used_by_stmt_p (stmt=0x7ffff6790630,
ref=0x7ffff6848048) at ../../src/gcc/tree-ssa-alias.c:1179
#9 0x00000000008bf275 in dse_possible_dead_store_p
(stmt=0x7ffff683e820, use_stmt=0x7fffffffdca8) at
../../src/gcc/tree-ssa-dse.c:212
#10 0x00000000008bfeb9 in dse_optimize_stmt (dse_gd=0x7fffffffddd0,
bd=0x156bd30, gsi=...) at ../../src/gcc/tree-ssa-dse.c:297
#11 0x00000000008c029d in dse_enter_block (walk_data=0x7fffffffdde0,
bb=0x7ffff6a75068) at ../../src/gcc/tree-ssa-dse.c:370
#12 0x0000000000cc26a5 in walk_dominator_tree (walk_data=0x7fffffffdde0,
bb=0x7ffff6a75068) at ../../src/gcc/domwalk.c:185
#13 0x00000000008c0812 in tree_ssa_dse () at
../../src/gcc/tree-ssa-dse.c:430
#14 0x000000000073af0a in execute_one_pass (pass=0x13cced0) at
../../src/gcc/passes.c:1572
#15 0x000000000073b21a in execute_pass_list (pass=0x13cced0) at
../../src/gcc/passes.c:1627
#16 0x000000000073b238 in execute_pass_list (pass=0x1312720) at
../../src/gcc/passes.c:1628
#17 0x000000000086e372 in tree_rest_of_compilation
(fndecl=0x7ffff6b93500) at ../../src/gcc/tree-optimize.c:413
#18 0x00000000009fa7c5 in cgraph_expand_function (node=0x7ffff6be7000)
at ../../src/gcc/cgraphunit.c:1548
#19 0x00000000009faa49 in cgraph_expand_all_functions () at
../../src/gcc/cgraphunit.c:1627
#20 0x00000000009fb07e in cgraph_optimize () at
../../src/gcc/cgraphunit.c:1875
#21 0x00000000009f9461 in cgraph_finalize_compilation_unit () at
../../src/gcc/cgraphunit.c:1096
#22 0x00000000004a9e93 in c_write_global_declarations () at
../../src/gcc/c-decl.c:9519
#23 0x00000000008180d4 in compile_file () at ../../src/gcc/toplev.c:1065
#24 0x000000000081a1c5 in do_compile () at ../../src/gcc/toplev.c:2417
#25 0x000000000081a286 in toplev_main (argc=21, argv=0x7fffffffe0f8) at
../../src/gcc/toplev.c:2459
#26 0x0000000000519c6b in main (argc=21, argv=0x7fffffffe0f8) at
../../src/gcc/main.c:35
Thanks,
Hongtao
Purdue University
