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<p class="MsoNormal"><span style="color:black">Hi all:<o:p></o:p></span></p>
<p class="MsoNormal"><span style="color:black"><o:p> </o:p></span></p>
<p class="MsoNormal"><span style="color:black">We would like to propose a clang pragma directive to allow specialized section names.<br>
The semantics of it could be as follows. The pragma section name is declared in global<br>
scope. All global variables and functions get assigned to the corresponding specialized<br>
section name if one is present. With this feature, the following code:<br>
<br>
// foo.c<br>
#pragma bss_section(".bss.alpha")<br>
#pragma data_section(".data.beta")<br>
#pragma code_section(".code.gamma")<br>
#pragma const_section(".const.delta")<br>
int a;<br>
int b=2;<br>
const int d = 5;<br>
int c(){<br>
return d;<br>
}<br>
<br>
..will emit llvm-ir as:<br>
<br>
target triple = "armv7-arm-none-eabi"<br>
@a = global i32 0, section ".bss.alpha", align 4<br>
@b = global i32 2, section ".data.beta", align 4<br>
@d = constant i32 5, section ".const.delta", align 4<br>
<br>
; Function Attrs: noinline nounwind<br>
define i32 @c() #0 section ".code.gamma" {<br>
entry:<br>
ret i32 5<br>
}<br>
<br>
This pragma will be very useful for embedded code which<br>
need to control where the different sections are placed in memory.<br>
<br>
Microsoft -fms-extension provides similar feature, but our proposal is for a <br>
general use. Attributes are an alternative that is also currently available,<br>
but attributes are applicable only to specific declarations and not entire<br>
file. Many real embedded users prefer the pragma option.<br>
This will be a welcome enabler for them. Also, </span>AUTOSAR, which is an<o:p></o:p></p>
<p class="MsoNormal">automotive standard mandates use of a #pragma solution over an attribute one<span style="color:black"><br>
<br>
Looking forward to comments and suggestions.<br>
</span>Best Regards<o:p></o:p></p>
<p class="MsoNormal">Javed<o:p></o:p></p>
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