[PATCH] D41742: [MSF] Fix FPM interval calculation

[Colden Cullen via Phabricator via llvm-commits]

colden added a comment.

Makes sense! Thanks for adding a test btw.

I tested this with my use-case, and it does indeed fix the problem.



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Comment at: llvm/include/llvm/DebugInfo/MSF/MSFCommon.h:118
+    // the number of fpm blocks.
+    int N = AltFpm ? 2 : 1;
+    return divideCeil(NumBlocks - N, BlockSize);
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Naming nitpick: In other contexts, `AltFpm` implies the opposite of `Msf.SB->FreeBlockMapBlock` (i.e. `3 - FpmBlock`). How about instead of taking that param here, you take an int for `FpmIndex` (or something), require it be 1 or 2, and then in the `MSFLayout` overload you can do the `AltFpm` transformation?


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Comment at: llvm/include/llvm/DebugInfo/MSF/MSFCommon.h:119
+    int N = AltFpm ? 2 : 1;
+    return divideCeil(NumBlocks - N, BlockSize);
+  }
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Ah, so I was almost right! Just didn't need the +1 on `BlockSize`.


https://reviews.llvm.org/D41742