diff options
| -rw-r--r-- | gdb/s390-tdep.c | 58 | ||||
| -rw-r--r-- | gdb/testsuite/gdb.ada/array_return.exp | 8 | ||||
| -rw-r--r-- | gdb/testsuite/gdb.base/finish-pretty.exp | 8 |
3 files changed, 72 insertions, 2 deletions
diff --git a/gdb/s390-tdep.c b/gdb/s390-tdep.c index d4b9a24..3a672b3 100644 --- a/gdb/s390-tdep.c +++ b/gdb/s390-tdep.c @@ -40,6 +40,7 @@ #include "trad-frame.h" #include "value.h" #include "inferior.h" +#include "dwarf2/loc.h" #include "features/s390-linux32.c" #include "features/s390x-linux64.c" @@ -2119,6 +2120,62 @@ s390_return_value (struct gdbarch *gdbarch, struct value *function, return rvc; } +/* Try to get the value of DWARF_REG in FRAME at function entry. If successful, + return it as value of type VAL_TYPE. */ + +static struct value * +dwarf_reg_on_entry (int dwarf_reg, struct type *val_type, + const frame_info_ptr &frame) +{ + enum call_site_parameter_kind kind = CALL_SITE_PARAMETER_DWARF_REG; + union call_site_parameter_u kind_u = { .dwarf_reg = dwarf_reg }; + + try + { + return value_of_dwarf_reg_entry (val_type, frame, kind, kind_u); + } + catch (const gdb_exception_error &e) + { + if (e.error == NO_ENTRY_VALUE_ERROR) + return nullptr; + + throw; + } +} + +/* Both the 32-bit and 64-bit ABIs specify that values of some types are + returned in a storage buffer provided by the caller. Return the address of + that storage buffer, if possible. Implements the + gdbarch_get_return_buf_addr hook. */ + +static CORE_ADDR +s390_get_return_buf_addr (struct type *val_type, + const frame_info_ptr &cur_frame) +{ + /* The address of the storage buffer is provided as a hidden argument in + register r2. */ + int dwarf_reg = 2; + + /* The ABI does not guarantee that the register will not be changed while + executing the function. Hence, it cannot be assumed that it will still + contain the address of the storage buffer when execution reaches the end + of the function. + + Attempt to determine the value on entry using the DW_OP_entry_value DWARF + entries. This requires compiling the user program with -fvar-tracking. */ + struct value *val_on_entry + = dwarf_reg_on_entry (dwarf_reg, lookup_pointer_type (val_type), cur_frame); + + if (val_on_entry == nullptr) + { + warning ("Cannot determine the function return value.\n" + "Try compiling with -fvar-tracking."); + return 0; + } + + return value_as_address (val_on_entry); +} + /* Frame unwinding. */ /* Implement the stack_frame_destroyed_p gdbarch method. */ @@ -7197,6 +7254,7 @@ s390_gdbarch_init (struct gdbarch_info info, struct gdbarch_list *arches) set_gdbarch_dummy_id (gdbarch, s390_dummy_id); set_gdbarch_frame_align (gdbarch, s390_frame_align); set_gdbarch_return_value (gdbarch, s390_return_value); + set_gdbarch_get_return_buf_addr (gdbarch, s390_get_return_buf_addr); /* Frame handling. */ /* Stack grows downward. */ diff --git a/gdb/testsuite/gdb.ada/array_return.exp b/gdb/testsuite/gdb.ada/array_return.exp index c6edee1..d1fc2ac 100644 --- a/gdb/testsuite/gdb.ada/array_return.exp +++ b/gdb/testsuite/gdb.ada/array_return.exp @@ -19,7 +19,13 @@ require allow_ada_tests standard_ada_testfile p -if {[gdb_compile_ada "${srcfile}" "${binfile}" executable {debug}] != ""} { +set opts {} +lappend opts debug +if { [have_fvar_tracking] } { + lappend opts "additional_flags=-fvar-tracking" +} + +if {[gdb_compile_ada "${srcfile}" "${binfile}" executable $opts] != ""} { return -1 } diff --git a/gdb/testsuite/gdb.base/finish-pretty.exp b/gdb/testsuite/gdb.base/finish-pretty.exp index 44f3340..0b6bea6 100644 --- a/gdb/testsuite/gdb.base/finish-pretty.exp +++ b/gdb/testsuite/gdb.base/finish-pretty.exp @@ -18,7 +18,13 @@ standard_testfile -if { [prepare_for_testing "failed to prepare" $testfile $srcfile] } { +set opts {} +lappend opts debug +if { [have_fvar_tracking] } { + lappend opts "additional_flags=-fvar-tracking" +} + +if { [prepare_for_testing "failed to prepare" $testfile $srcfile $opts] } { return -1 } |