[PATCH] D66969: Output XCOFF object text section header and symbol entry for program code

[Sean Fertile via Phabricator via llvm-commits]

sfertile added a comment.

We need to verify if we need the storage padding or not before finalizing, but otherwise the patch looks pretty good.



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Comment at: llvm/lib/MC/XCOFFObjectWriter.cpp:69
   uint32_t Size;
+  uint32_t PaddingSize;
 
----------------
We might be able to skip writing the actual zeros for padding, and instead just pad out the virtual addresses assigned to the sections/csects. I believe @hubert.reinterpretcast was following up with one of the AIX system toolchain devs to verify.


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Comment at: llvm/lib/MC/XCOFFObjectWriter.cpp:537
     BSS.Index = SectionIndex++;
-    assert(alignTo(Address, DefaultSectionAlign) == Address &&
-           "Improperly aligned address for section.");
-    uint32_t StartAddress = Address;
+    // We use alignment Address of previous section as BSS start Address, it
+    // maybe not need.
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I'm sorry Digger, but I am having trouble figuring out what the comment is trying to convey.

Is it that each section is padded out to `DefaultSectionAlign` so that `Address` must be properly aligned already?

Is it trying to explain how we don't have to align the sections virtual address anymore then `DefaultSectionAlign` (even when contained csects may be more strictly aligned then that) becuase the sections alignment is immaterial? 


Repository:
  rL LLVM

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https://reviews.llvm.org/D66969