From: "Joey Ye" <joey.ye@arm.com>
To: "Richard Earnshaw" <Richard.Earnshaw@arm.com>
Cc: <gcc-patches@gcc.gnu.org>
Subject: RE: [patch] [arm] New option for PIC offset unfixed
Date: Wed, 13 Nov 2013 17:23:00 -0000 [thread overview]
Message-ID: <000101cee08a$ba5b5720$2f120560$@arm.com> (raw)
In-Reply-To: <52835D38.4020309@arm.com>
[-- Attachment #1: Type: text/plain, Size: 1060 bytes --]
This patch address all comments.
Thanks,
Joey
> -----Original Message-----
> From: Richard Earnshaw
> Sent: Wednesday, November 13, 2013 19:07
> To: Joey Ye
> Cc: gcc-patches@gcc.gnu.org
> Subject: Re: [patch] [arm] New option for PIC offset unfixed
>
> On 13/11/13 10:20, Joey Ye wrote:
> >>> +@item -mpic-data-is-text-relative
> >>> > > +@opindex mpic-data-is-text-relative Assume that each data
> >>> > > +segments are relative to text segment at load
> > time.
> >> >
> >>> > > +Therefore, prevent PC relative and GOTOFF style relocations to
> >>> > > +reference data.
> >> >
> >> > I think the sense of this sentence is now backwards. I'd also try
> >> > to
> > avoid
> >> > GOTOFF in the user part of the manual.
> > How about
> > "Therefore, prevent addressing data with relocation types that doesn't
> > apply in such circumstance."
> >
> >> >
>
> No, that's still backwards. Remember, the option is now pic-data-is-text-
> relative, so the option /permits/ addressing data using PC-relative
operations.
>
> R.
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diff --git a/gcc/config/arm/arm.c b/gcc/config/arm/arm.c
index 7757e86..5a95399 100644
--- a/gcc/config/arm/arm.c
+++ b/gcc/config/arm/arm.c
@@ -2504,6 +2504,11 @@ arm_option_override (void)
arm_pic_register = pic_register;
}
+ if (arm_pic_data_is_text_relative < 0 && TARGET_VXWORKS_RTP)
+ arm_pic_data_is_text_relative = 0;
+ else
+ arm_pic_data_is_text_relative = 1;
+
/* Enable -mfix-cortex-m3-ldrd by default for Cortex-M3 cores. */
if (fix_cm3_ldrd == 2)
{
@@ -6020,7 +6025,7 @@ legitimize_pic_address (rtx orig, enum machine_mode mode, rtx reg)
|| (GET_CODE (orig) == SYMBOL_REF &&
SYMBOL_REF_LOCAL_P (orig)))
&& NEED_GOT_RELOC
- && !TARGET_VXWORKS_RTP)
+ && arm_pic_data_is_text_relative)
insn = arm_pic_static_addr (orig, reg);
else
{
@@ -21498,7 +21503,7 @@ arm_assemble_integer (rtx x, unsigned int size, int aligned_p)
{
/* See legitimize_pic_address for an explanation of the
TARGET_VXWORKS_RTP check. */
- if (TARGET_VXWORKS_RTP
+ if (!arm_pic_data_is_text_relative
|| (GET_CODE (x) == SYMBOL_REF && !SYMBOL_REF_LOCAL_P (x)))
fputs ("(GOT)", asm_out_file);
else
diff --git a/gcc/config/arm/arm.opt b/gcc/config/arm/arm.opt
index 9b74038..adac749 100644
--- a/gcc/config/arm/arm.opt
+++ b/gcc/config/arm/arm.opt
@@ -158,6 +158,10 @@ mlong-calls
Target Report Mask(LONG_CALLS)
Generate call insns as indirect calls, if necessary
+mpic-data-is-text-relative
+Target Report Var(arm_pic_data_is_text_relative) Init(-1)
+Assume data segments are relative to text segment.
+
mpic-register=
Target RejectNegative Joined Var(arm_pic_register_string)
Specify the register to be used for PIC addressing
diff --git a/gcc/doc/invoke.texi b/gcc/doc/invoke.texi
index 863e518..fbe77e6 100644
--- a/gcc/doc/invoke.texi
+++ b/gcc/doc/invoke.texi
@@ -12120,6 +12120,12 @@ before execution begins.
Specify the register to be used for PIC addressing. The default is R10
unless stack-checking is enabled, when R9 is used.
+@item -mpic-data-is-text-relative
+@opindex mpic-data-is-text-relative
+Assume that each data segments are relative to text segment at load time.
+Therefore, it permits addressing data using PC-relative operations.
+This option is on by default for targets other than VxWorks RTP.
+
@item -mpoke-function-name
@opindex mpoke-function-name
Write the name of each function into the text section, directly
next prev parent reply other threads:[~2013-11-13 16:09 UTC|newest]
Thread overview: 12+ messages / expand[flat|nested] mbox.gz Atom feed top
2013-11-12 10:12 Joey Ye
2013-11-12 13:37 ` Richard Earnshaw
2013-11-13 9:06 ` Joey Ye
2013-11-13 10:52 ` Richard Earnshaw
2013-11-13 11:16 ` Joey Ye
2013-11-13 11:46 ` Richard Earnshaw
2013-11-13 17:23 ` Joey Ye [this message]
2013-11-13 12:21 ` Richard Earnshaw
[not found] ` <45520D6299C11E4588128526465332BB3BDBAD147A@SAROVARA.Asiapac.Arm.com>
2013-11-13 18:00 ` Richard Earnshaw
2013-11-14 10:09 Joey Ye
2013-11-14 10:48 ` Richard Earnshaw
2013-11-14 12:53 ` Joey Ye
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