From: Dominik Vogt <vogt@linux.vnet.ibm.com>
To: gdb-patches@sourceware.org
Subject: Re: [PATCH 1/2] Fix invalid left shift of negative value.
Date: Tue, 10 Nov 2015 11:17:00 -0000 [thread overview]
Message-ID: <20151110111709.GE17214@linux.vnet.ibm.com> (raw)
In-Reply-To: <20151110111638.GD17214@linux.vnet.ibm.com>
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On Tue, Nov 10, 2015 at 12:16:38PM +0100, Dominik Vogt wrote:
> The following series of patches fixes all occurences of
> left-shifting negative constants in C code which is undefined by
> the C standard. The patches have been tested on s390x, covering
> only a small subset of the changes.
Changes in gdb/.
Ciao
Dominik ^_^ ^_^
--
Dominik Vogt
IBM Germany
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From f0480d41f3036d193513fa4dfbba414201b610ec Mon Sep 17 00:00:00 2001
From: Dominik Vogt <vogt@linux.vnet.ibm.com>
Date: Fri, 30 Oct 2015 15:17:22 +0100
Subject: [PATCH 1/2] gdb: Fix left shift of negative value.
This patch fixes all occurences of left-shifting negative constants in C cod
which is undefined by the C standard.
gdb/ChangeLog:
* hppa-tdep.c (hppa_sign_extend, hppa_low_hppa_sign_extend)
(prologue_inst_adjust_sp, hppa_frame_cache): Fix left shift of negative
value.
* dwarf2read.c (read_subrange_type): Likewise.
---
gdb/ChangeLog | 7 +++++++
gdb/dwarf2read.c | 2 +-
gdb/hppa-tdep.c | 8 ++++----
2 files changed, 5 insertions(+), 5 deletions(-)
diff --git a/gdb/dwarf2read.c b/gdb/dwarf2read.c
index 87dc8b4..48921e7 100644
--- a/gdb/dwarf2read.c
+++ b/gdb/dwarf2read.c
@@ -15048,7 +15048,7 @@ read_subrange_type (struct die_info *die, struct dwarf2_cu *cu)
the bounds as signed, and thus sign-extend their values, when
the base type is signed. */
negative_mask =
- (LONGEST) -1 << (TYPE_LENGTH (base_type) * TARGET_CHAR_BIT - 1);
+ -((LONGEST) 1 << (TYPE_LENGTH (base_type) * TARGET_CHAR_BIT - 1));
if (low.kind == PROP_CONST
&& !TYPE_UNSIGNED (base_type) && (low.data.const_val & negative_mask))
low.data.const_val |= negative_mask;
diff --git a/gdb/hppa-tdep.c b/gdb/hppa-tdep.c
index ba7f946..3206729 100644
--- a/gdb/hppa-tdep.c
+++ b/gdb/hppa-tdep.c
@@ -104,7 +104,7 @@ static const struct objfile_data *hppa_objfile_priv_data = NULL;
static int
hppa_sign_extend (unsigned val, unsigned bits)
{
- return (int) (val >> (bits - 1) ? (-1 << bits) | val : val);
+ return (int) (val >> (bits - 1) ? (-(1 << bits)) | val : val);
}
/* For many immediate values the sign bit is the low bit! */
@@ -112,7 +112,7 @@ hppa_sign_extend (unsigned val, unsigned bits)
static int
hppa_low_hppa_sign_extend (unsigned val, unsigned bits)
{
- return (int) ((val & 0x1 ? (-1 << (bits - 1)) : 0) | val >> 1);
+ return (int) ((val & 0x1 ? (-(1 << (bits - 1))) : 0) | val >> 1);
}
/* Extract the bits at positions between FROM and TO, using HP's numbering
@@ -1357,7 +1357,7 @@ prologue_inst_adjust_sp (unsigned long inst)
/* std,ma X,D(sp) */
if ((inst & 0xffe00008) == 0x73c00008)
- return (inst & 0x1 ? -1 << 13 : 0) | (((inst >> 4) & 0x3ff) << 3);
+ return (inst & 0x1 ? -(1 << 13) : 0) | (((inst >> 4) & 0x3ff) << 3);
/* addil high21,%r30; ldo low11,(%r1),%r30)
save high bits in save_high21 for later use. */
@@ -2066,7 +2066,7 @@ hppa_frame_cache (struct frame_info *this_frame, void **this_cache)
CORE_ADDR offset;
if ((inst >> 26) == 0x1c)
- offset = (inst & 0x1 ? -1 << 13 : 0)
+ offset = (inst & 0x1 ? -(1 << 13) : 0)
| (((inst >> 4) & 0x3ff) << 3);
else if ((inst >> 26) == 0x03)
offset = hppa_low_hppa_sign_extend (inst & 0x1f, 5);
--
2.3.0
next prev parent reply other threads:[~2015-11-10 11:17 UTC|newest]
Thread overview: 14+ messages / expand[flat|nested] mbox.gz Atom feed top
2015-11-10 11:16 [PATCH 0/2] " Dominik Vogt
2015-11-10 11:17 ` Dominik Vogt [this message]
2015-11-10 11:18 ` [PATCH 2/2] " Dominik Vogt
2015-11-10 22:42 ` [PATCH 0/2] " Kevin Buettner
2015-11-11 17:23 ` Ulrich Weigand
2015-11-11 19:27 ` Kevin Buettner
2015-11-17 5:09 ` Kevin Buettner
2015-11-17 14:13 ` Pedro Alves
2015-11-17 17:33 ` Paul_Koning
2015-11-17 15:10 ` [PATCH 3/2] " Dominik Vogt
2015-11-17 17:49 ` Kevin Buettner
2015-11-30 8:54 ` Dominik Vogt
2015-12-06 14:17 ` [SIM patch] " Joel Brobecker
2015-12-15 13:15 ` Andreas Arnez
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