[llvm] [WIP] Extend data layout to add non zero null value for address space. (PR #83109)

[Rana Pratap Reddy via llvm-commits]

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@@ -3076,6 +3084,7 @@ specifications are given in this list:
 -  ``v64:64:64`` - 64-bit vector is 64-bit aligned
 -  ``v128:128:128`` - 128-bit vector is 128-bit aligned
 -  ``a:0:64`` - aggregates are 64-bit aligned
+-  ``z:0`` - default null value of 0 for unlisted(INT_MAX) address space
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ranapratap55 wrote:

Unlisted here means, for address spaces which are not specified in the data layout string.

https://github.com/llvm/llvm-project/pull/83109