From: Victor Collod <vcollod@nvidia.com>
To: <gdb-patches@sourceware.org>
Subject: [PATCH v3 2/7] amd64_analyze_prologue: swap upper bound check condition operands
Date: Tue, 23 Jun 2020 18:28:52 -0700 [thread overview]
Message-ID: <20200624012857.31849-3-vcollod@nvidia.com> (raw)
In-Reply-To: <20200624012857.31849-1-vcollod@nvidia.com>
`if (current_pc <= pc)' felt backwards, as current_pc doesn't change,
and the test could be described as "stop if pc went past current_pc".
2020-06-23 Victor Collod <vcollod@nvidia.com>
* amd64-tdep.c (amd64_analyze_prologue): Swap upper bound check
condition operands.
---
gdb/amd64-tdep.c | 10 ++++++----
1 file changed, 6 insertions(+), 4 deletions(-)
diff --git a/gdb/amd64-tdep.c b/gdb/amd64-tdep.c
index 0ce9fbc2997..ff12cb874b8 100644
--- a/gdb/amd64-tdep.c
+++ b/gdb/amd64-tdep.c
@@ -2387,7 +2387,8 @@ amd64_analyze_prologue (struct gdbarch *gdbarch,
gdb_byte buf[3];
gdb_byte op;
- if (current_pc <= pc)
+ /* Analysis must not go past current_pc. */
+ if (pc >= current_pc)
return current_pc;
if (gdbarch_ptr_bit (gdbarch) == 32)
@@ -2408,7 +2409,8 @@ amd64_analyze_prologue (struct gdbarch *gdbarch,
op = read_code_unsigned_integer (pc, 1, byte_order);
}
- if (current_pc <= pc)
+ /* If we went past the allowed bound, stop. */
+ if (pc >= current_pc)
return current_pc;
if (op == 0x55) /* pushq %rbp */
@@ -2418,8 +2420,8 @@ amd64_analyze_prologue (struct gdbarch *gdbarch,
cache->saved_regs[AMD64_RBP_REGNUM] = 0;
cache->sp_offset += 8;
- /* If that's all, return now. */
- if (current_pc <= pc + 1)
+ /* If we went past the allowed bound, stop. */
+ if (pc + 1 >= current_pc)
return current_pc;
read_code (pc + 1, buf, 3);
--
2.20.1
next prev parent reply other threads:[~2020-06-24 1:29 UTC|newest]
Thread overview: 26+ messages / expand[flat|nested] mbox.gz Atom feed top
2020-06-05 23:23 [PATCH] Improve intel IBT support Victor Collod
2020-06-05 23:55 ` Victor Collod
2020-06-11 3:18 ` Simon Marchi
2020-06-11 22:54 ` [PATCH v2 0/2] " Victor Collod
2020-06-11 22:54 ` [PATCH v2 1/2] Add i386 support for endbr skipping Victor Collod
2020-06-21 11:27 ` Simon Marchi
2020-06-11 22:54 ` [PATCH v2 2/2] Refactor amd64_analyze_prologue Victor Collod
2020-06-21 11:38 ` Simon Marchi
2020-06-24 1:28 ` [PATCH v3 0/7] Improve intel IBT support Victor Collod
2020-06-24 1:28 ` [PATCH v3 1/7] Add i386 support for endbr skipping Victor Collod
2020-08-06 13:57 ` Simon Marchi
2020-09-19 0:29 ` [PATCH] gdb: Update i386_analyze_prologue to skip endbr32 H.J. Lu
2020-09-19 0:38 ` Simon Marchi
2020-06-24 1:28 ` Victor Collod [this message]
2020-08-06 14:41 ` [PATCH v3 2/7] amd64_analyze_prologue: swap upper bound check condition operands Simon Marchi
2020-06-24 1:28 ` [PATCH v3 3/7] amd64_analyze_prologue: merge op and buf Victor Collod
2020-08-06 14:55 ` Simon Marchi
2020-06-24 1:28 ` [PATCH v3 4/7] amd64_analyze_prologue: invert a condition for readability Victor Collod
2020-08-06 14:57 ` Simon Marchi
2020-06-24 1:28 ` [PATCH v3 5/7] amd64_analyze_prologue: gradually update pc Victor Collod
2020-08-06 14:59 ` Simon Marchi
2020-06-24 1:28 ` [PATCH v3 6/7] amd64_analyze_prologue: fix incorrect comment Victor Collod
2020-08-06 15:05 ` Simon Marchi
2020-06-24 1:28 ` [PATCH v3 7/7] amd64_analyze_prologue: use target_read_code instead of read_code Victor Collod
2020-08-06 15:01 ` Simon Marchi
2020-08-05 21:44 ` [PATCH v3 0/7] Improve intel IBT support Victor Collod
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