From fcaa1071d7921c4f7c7592a10ed7b84830ec8c49 Mon Sep 17 00:00:00 2001 From: Christophe Lyon Date: Fri, 1 Apr 2022 10:21:58 +0100 Subject: [PATCH] gdb/arm: Fix prologue analysis to support vpush While working on adding support for Non-secure/Secure modes unwinding, I noticed that the prologue analysis lacked support for vpush, which is used for instance in the CMSE stub routine. This patch updates thumb_analyze_prologue accordingly, adding support for vpush of D-registers. Signed-off-by: Christophe Lyon Signed-off-by: Christophe Lyon --- gdb/arm-tdep.c | 29 +++++++++++++++++++++++++++++ 1 file changed, 29 insertions(+) diff --git a/gdb/arm-tdep.c b/gdb/arm-tdep.c index cc7773914d7..66e26e6e212 100644 --- a/gdb/arm-tdep.c +++ b/gdb/arm-tdep.c @@ -902,6 +902,35 @@ thumb_analyze_prologue (struct gdbarch *gdbarch, regs[bits (insn, 0, 3)] = addr; } + /* vstmdb Rn{!}, { D-registers } (aka vpush). */ + else if ((insn & 0xff20) == 0xed20 + && (inst2 & 0x0f00) == 0x0b00 + && pv_is_register (regs[bits (insn, 0, 3)], ARM_SP_REGNUM)) + { + /* Address SP points to. */ + pv_t addr = regs[bits (insn, 0, 3)]; + + /* Number of registers saved. */ + unsigned int number = bits (inst2, 0, 7) >> 1; + + /* First register to save. */ + int vd = bits (inst2, 12, 15) | (bits (insn, 6, 6) << 4); + + if (stack.store_would_trash (addr)) + break; + + /* Calculate offsets of saved registers. */ + for (; number > 0; number--) + { + addr = pv_add_constant (addr, -8); + stack.store (addr, 8, pv_register (ARM_D0_REGNUM + + vd + number, 0)); + } + + /* Writeback SP to account for the saved registers. */ + regs[bits (insn, 0, 3)] = addr; + } + else if ((insn & 0xff50) == 0xe940 /* strd Rt, Rt2, [Rn, #+/-imm]{!} */ && pv_is_register (regs[bits (insn, 0, 3)], ARM_SP_REGNUM)) -- 2.30.2