[PATCH] D37798: Teach TargetInstrInfo::getInlineAsmLength to parse .space directives with integer arguments

[Simon Dardis via Phabricator via llvm-commits]

sdardis requested changes to this revision.
sdardis added inline comments.
This revision now requires changes to proceed.


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Comment at: lib/CodeGen/TargetInstrInfo.cpp:104-107
+        while (isspace(static_cast<unsigned char>(*EStr)))
+          ++EStr;
+        if (*EStr == '\0') // Successfully parsed .space argument
+          AddLength = SpaceSize;
----------------
This code has unexpected behaviour in that it accepts a mixture of zero or more things that look like instructions or comments __ending__ with an optional .space <int> directive. If the .space directive is parsed and there is not zero or more spaces followed by the null byte, the value of space is discarded even if it was a positive number.

This bug was present in the original version, but it didn't occur to my knowledge as ".space <num>" was the only form used as far as I can see.

I think it is better to parse this properly so that people don't get tripped up over when trying to use this.

Aside: we may also want to handle .align, .fill at some point.


https://reviews.llvm.org/D37798