commit 03dabcdca5606e67a484ddd41571590e2a027005
author dan sinclair <dsinclair@chromium.org> Tue Apr 01 08:43:40 2025 -0700
committer Dawn LUCI CQ <dawn-scoped@luci-project-accounts.iam.gserviceaccount.com> Tue Apr 01 08:43:40 2025 -0700
tree 7099302f8e8c6d9de0db1be74703dcd1c5c7a896
parent ffa03675bbdd3fe92e309ce44dcd3159483baa41

Revert "Range Analysis: Get loop exit condition from body block"

This reverts commit 1411699ba4cdf29eca037c4320543ab8189bad28.

Reason for revert: Crashing on the cmake-linux-clang-dbg-x64-ubsan bot

[ RUN      ] IR_IntegerRangeAnalysisTest.AnalyzeLoopBody_Failure_Index_LessThan_Min_I32
/b/s/w/ir/cache/uncached/dawn/src/tint/lang/core/number.h:176:46: runtime error: negation of -2147483648 cannot be represented in type 'type' (aka 'int'); cast to an unsigned type to negate this value to itself
   

Original change's description:
> Range Analysis: Get loop exit condition from body block
>
> This patch is the third part to implement the computation of the
> range on the loop control variables. In this patch we implement the
> function `GetBinaryToCompareLoopControlVariableInLoopBody()` to get
> the condition to exit the loop in the loop body block if the loop
> meets the below requirements (a straightforward for-loop):
> - The loop control variable is only used as the parameter of the
>   load instruction.
> - The first instruction is to load the loop control variable into a
>   temporary variable.
> - The second instruction is to compare the temporary variable with
>   a constant value and save the result to a boolean variable.
> - The second instruction cannot be a comparison that will never be
>   true (out of range of 32-bit integer).
> - The third instruction is an `ifelse` expression that uses the
>   boolean variable got in the second instruction as the condition.
> - The true block of the above `ifelse` expression doesn't contain
>   `exit_loop`.
> - The false block of the above `ifelse` expression only contains
>   `exit_loop`.
>
> Bug: chromium:348701956
> Test: tint_unittests
> Change-Id: Ie99911791eb6530e6d081ac9b54c2ec74e1be64c
> Reviewed-on: https://dawn-review.googlesource.com/c/dawn/+/233294
> Commit-Queue: Jiawei Shao <jiawei.shao@intel.com>
> Reviewed-by: James Price <jrprice@google.com>

TBR=jiawei.shao@intel.com,dneto@google.com,jrprice@google.com,dawn-scoped@luci-project-accounts.iam.gserviceaccount.com

No-Presubmit: true
No-Tree-Checks: true
No-Try: true
Bug: chromium:348701956
Change-Id: Idf151f39c2b25d66d0ce40dd31300735f3aabf76
Reviewed-on: https://dawn-review.googlesource.com/c/dawn/+/234094
Reviewed-by: James Price <jrprice@google.com>
Commit-Queue: James Price <jrprice@google.com>
Reviewed-by: dan sinclair <dsinclair@chromium.org>
Auto-Submit: dan sinclair <dsinclair@chromium.org>