public inbox for binutils@sourceware.org
 help / color / mirror / Atom feed
* [PATCH 0/3] RISC-V: Fix address printer on the disassembler
@ 2022-07-29 13:10 Tsukasa OI
  2022-07-29 13:10 ` [PATCH 1/3] RISC-V: Print highest address on disassembler Tsukasa OI
                   ` (3 more replies)
  0 siblings, 4 replies; 48+ messages in thread
From: Tsukasa OI @ 2022-07-29 13:10 UTC (permalink / raw)
  To: Tsukasa OI, H . Peter Anvin, Nelson Chu, Kito Cheng, Palmer Dabbelt
  Cc: binutils

Hello,

This patchset contains a fix to PR29342.

Tracker on GitHub:
<https://github.com/a4lg/binutils-gdb/wiki/riscv_dis_fix_addr>

Original Issue as reported by H. Peter Anvin:
<https://sourceware.org/bugzilla/show_bug.cgi?id=29342>

First of all, this bug is caused by address computation of maybe_print_address
on disassembling RV32 programs.

Let me show the pseudocode of `maybe_print_address':

    if (high part of the register [for address sequence] is set)
    {
        pd->print_addr = (high part) + offset;        // (1)
        unset high part (as used);
    }
    else if (base register == `gp' && __global_pointer$ is available)
        pd->print_addr = __global_pointer$ + offset;  // (2)
    else if (base register == `tp' || base register == `zero')
        pd->print_addr = offset;                      // (3)
    // Sign-extend a 32-bit value to 64-bit
    if (instruction is ADDIW or C.ADDIW)
        pd->print_addr = (bfd_vma)(int32_t)pd->print_addr;

In here, it implicitly sign-extends an `int'-typed variable `offset' to generate
an address.  (3) is the direct cause of PR29342 but other locations have
similar issue.

On an example provided by Peter, IOREG_FOO has an address value of 0xffffff00.
However, due to incorrect sign-extension, the disassembler considers that the
`sw' instruction operates on an incorrect address 0xffffffff_ffffff00 EVEN ON
RV32.  This affects symbol lookup.  So, we have to mask (and zero-extend) the
address on RV32 to get correct address 0xffffff00.

Also, the background provided by Peter gives us a context: highest address space
may be important for some systems/programs.  So, not only fixing PR29342, I
decided to make the address -1 (originally reserved as a non-printing address)
printable by separating (a) the address to print and (b) whether the address
should be printed.  This isn't zero-overhead but close to.

This patchset:

1.  fits an address into a 32-bit value on RV32 (resolves PR29342)
2.  makes the highest address printable
    (0xffffffff can be printed as a real symbol)
3.  clarifies the meaning of the `wide' argument
    (`is_addiw' fits the context).

It also has new testcases and a testcase modification (it seems lla32.d is
affected by this patchset but not harmful so that modifying the testcase
lla32.d seemed better).

Thanks,
Tsukasa




Tsukasa OI (3):
  RISC-V: Print highest address on disassembler
  RISC-V: Fix RV32 disassembler address computation
  RISC-V: Add address printer tests on disassembler

 gas/testsuite/gas/riscv/dis-addr-1-32.d | 29 ++++++++++
 gas/testsuite/gas/riscv/dis-addr-1-64.d | 33 ++++++++++++
 gas/testsuite/gas/riscv/dis-addr-1.s    | 70 +++++++++++++++++++++++++
 gas/testsuite/gas/riscv/lla32.d         |  2 +-
 opcodes/riscv-dis.c                     | 34 +++++++-----
 5 files changed, 154 insertions(+), 14 deletions(-)
 create mode 100644 gas/testsuite/gas/riscv/dis-addr-1-32.d
 create mode 100644 gas/testsuite/gas/riscv/dis-addr-1-64.d
 create mode 100644 gas/testsuite/gas/riscv/dis-addr-1.s


base-commit: b245c595aaa59812f8f3a0e8b70ea5f52e045627
-- 
2.34.1


^ permalink raw reply	[flat|nested] 48+ messages in thread

end of thread, other threads:[~2022-08-25  5:07 UTC | newest]

Thread overview: 48+ messages (download: mbox.gz / follow: Atom feed)
-- links below jump to the message on this page --
2022-07-29 13:10 [PATCH 0/3] RISC-V: Fix address printer on the disassembler Tsukasa OI
2022-07-29 13:10 ` [PATCH 1/3] RISC-V: Print highest address on disassembler Tsukasa OI
2022-07-29 13:10 ` [PATCH 2/3] RISC-V: Fix RV32 disassembler address computation Tsukasa OI
2022-07-29 13:10 ` [PATCH 3/3] RISC-V: Add address printer tests on disassembler Tsukasa OI
2022-08-02  5:54 ` [PATCH v2 0/4] RISC-V: Fix address printer on the disassembler Tsukasa OI
2022-08-02  5:54   ` [PATCH v2 1/4] RISC-V: Print highest address on disassembler Tsukasa OI
2022-08-02  5:54   ` [PATCH v2 2/4] RISC-V: Fix RV32 disassembler address computation Tsukasa OI
2022-08-02  5:54   ` [PATCH v2 3/4] RISC-V: Break early if RISCV_GP_SYMBOL is found Tsukasa OI
2022-08-02  5:54   ` [PATCH v2 4/4] RISC-V: Add address printer tests on disassembler Tsukasa OI
2022-08-04  4:35   ` [PATCH v3 0/3] RISC-V: Fix address printer on the disassembler Tsukasa OI
2022-08-04  4:35     ` [PATCH v3 1/3] RISC-V: Print highest address on disassembler Tsukasa OI
2022-08-04  4:35     ` [PATCH v3 2/3] RISC-V: Fix RV32 disassembler address computation Tsukasa OI
2022-08-04  4:35     ` [PATCH v3 3/3] RISC-V: Add address printer tests on disassembler Tsukasa OI
2022-08-08 18:31     ` [PATCH v3 0/3] RISC-V: Fix address printer on the disassembler H. Peter Anvin
2022-08-08 19:46       ` Palmer Dabbelt
2022-08-09  3:39     ` [PATCH v3 0/4] " Tsukasa OI
2022-08-09  3:39       ` [PATCH v3 1/4] RISC-V: Print highest address on disassembler Tsukasa OI
2022-08-09  3:39       ` [PATCH v3 2/4] RISC-V: Fix RV32 disassembler address computation Tsukasa OI
2022-08-09  3:39       ` [PATCH v3 3/4] RISC-V: Fix JALR target " Tsukasa OI
2022-08-09  3:39       ` [PATCH v3 4/4] RISC-V: Add address printer tests on disassembler Tsukasa OI
2022-08-09  3:44     ` [PATCH v4 0/4] RISC-V: Fix address printer on the disassembler Tsukasa OI
2022-08-09  3:44       ` [PATCH v4 1/4] RISC-V: Print highest address on disassembler Tsukasa OI
2022-08-09  3:44       ` [PATCH v4 2/4] RISC-V: Fix RV32 disassembler address computation Tsukasa OI
2022-08-09  3:44       ` [PATCH v4 3/4] RISC-V: Fix JALR target " Tsukasa OI
2022-08-09  3:44       ` [PATCH v4 4/4] RISC-V: Add address printer tests on disassembler Tsukasa OI
2022-08-09  4:41       ` [PATCH v5 0/4] RISC-V: Fix address printer on the disassembler Tsukasa OI
2022-08-09  4:41         ` [PATCH v5 1/4] RISC-V: Print highest address on disassembler Tsukasa OI
2022-08-09  4:41         ` [PATCH v5 2/4] RISC-V: Fix RV32 disassembler address computation Tsukasa OI
2022-08-09  4:41         ` [PATCH v5 3/4] RISC-V: Fix JALR target " Tsukasa OI
2022-08-09  4:41         ` [PATCH v5 4/4] RISC-V: Add address printer tests on disassembler Tsukasa OI
2022-08-13 10:10         ` [PATCH v6 0/4] RISC-V: Fix address printer on the disassembler Tsukasa OI
2022-08-13 10:10           ` [PATCH v6 1/4] RISC-V: Print highest address on disassembler Tsukasa OI
2022-08-13 10:10           ` [PATCH v6 2/4] RISC-V: Fix RV32 disassembler address computation Tsukasa OI
2022-08-13 10:10           ` [PATCH v6 3/4] RISC-V: Fix JALR target " Tsukasa OI
2022-08-13 10:10           ` [PATCH v6 4/4] RISC-V: Add address printer tests on disassembler Tsukasa OI
2022-08-24  1:26           ` [PATCH v7 0/5] RISC-V: Fix address printer on the disassembler Tsukasa OI
2022-08-24  1:26             ` [PATCH v7 1/5] RISC-V: Print highest address on disassembler Tsukasa OI
2022-08-24 11:22               ` Nelson Chu
2022-08-24 11:22                 ` Nelson Chu
2022-08-24 12:06                 ` Tsukasa OI
2022-08-25  5:07                   ` Nelson Chu
2022-08-24  1:26             ` [PATCH v7 2/5] RISC-V: Fix RV32 disassembler address computation Tsukasa OI
2022-08-24 11:35               ` Nelson Chu
2022-08-24  1:26             ` [PATCH v7 3/5] RISC-V: Fix JALR target " Tsukasa OI
2022-08-24 11:36               ` Nelson Chu
2022-08-24  1:26             ` [PATCH v7 4/5] RISC-V: Add address printer tests on disassembler Tsukasa OI
2022-08-24 11:42               ` Nelson Chu
2022-08-24  1:26             ` [PATCH v7 5/5] RISC-V: Add address printer tests with ADDIW Tsukasa OI

This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox;
as well as URLs for read-only IMAP folder(s) and NNTP newsgroup(s).