commit c6236e830e88de072235dbf1caab8def6cc47ab4
author Jiawei Shao <jiawei.shao@intel.com> Wed Apr 02 13:33:20 2025 -0700
committer Dawn LUCI CQ <dawn-scoped@luci-project-accounts.iam.gserviceaccount.com> Wed Apr 02 13:33:20 2025 -0700
tree fbba521e1322f2cdd19ea3ad61ab4a69fb9d9e92
parent 388f632c14a6479ce7aa22772d0c72c28d4c1025

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

This is a reland of commit 1411699ba4cdf29eca037c4320543ab8189bad28

This patch uses `std::numeric_limits<int32_t>::max()` instead of
`-2147483648_i` in the tests to fix the error that uses `-` on
`2147483648` as an `int32_t`.

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>

Bug: chromium:348701956
Change-Id: Idf4ccfab7961fa68d7d5c62f1555c81cbfa73fb6
Reviewed-on: https://dawn-review.googlesource.com/c/dawn/+/234275
Commit-Queue: James Price <jrprice@google.com>
Reviewed-by: James Price <jrprice@google.com>
Reviewed-by: dan sinclair <dsinclair@chromium.org>