[Mlir-commits] [mlir] [mlir][ArmNeon] Enable native I8MM integration testing on Darwin (PR #216098)

[Federico Bruzzone]

https://github.com/FedericoBruzzone updated https://github.com/llvm/llvm-project/pull/216098

>From 20580fb344400c5ef549d9559c61f9ead703ffd9 Mon Sep 17 00:00:00 2001
From: Federico Bruzzone <federico.bruzzone.i at gmail.com>
Date: Thu, 13 Aug 2026 17:57:58 +0200
Subject: [PATCH 1/3] [mlir][ArmNeon] Enable native I8MM integration testing on
 Darwin

Signed-off-by: Federico Bruzzone <federico.bruzzone.i at gmail.com>
---
 .../modules/MLIRCheckHardwareFeatures.cmake   | 31 +++++++++++++++++--
 .../CPU/ArmNeon/vector-contract-i8mm.mlir     |  2 --
 2 files changed, 29 insertions(+), 4 deletions(-)

diff --git a/mlir/cmake/modules/MLIRCheckHardwareFeatures.cmake b/mlir/cmake/modules/MLIRCheckHardwareFeatures.cmake
index 3aea591d885f7..00555c0b53ced 100644
--- a/mlir/cmake/modules/MLIRCheckHardwareFeatures.cmake
+++ b/mlir/cmake/modules/MLIRCheckHardwareFeatures.cmake
@@ -26,6 +26,31 @@ function(check_sme_support_on_darwin output)
     set(${output} ${local_result} PARENT_SCOPE)
 endfunction(check_sme_support_on_darwin)
 
+# Checks whether I8MM is supported by the host Darwin (macOS) system. This is
+# implemented via `sysctl`, since Darwin has no equivalent of Linux's
+# auxiliary vector feature bits (hwcap).
+#
+# check_i8mm_support_on_darwin(
+#   output_var
+# )
+function(check_i8mm_support_on_darwin output)
+    execute_process(
+        COMMAND sysctl -n hw.optional.arm.FEAT_I8MM
+        OUTPUT_VARIABLE sysctl_output
+        OUTPUT_STRIP_TRAILING_WHITESPACE
+        ERROR_QUIET
+        RESULT_VARIABLE sysctl_result
+    )
+
+    if(sysctl_result EQUAL 0 AND sysctl_output STREQUAL "1")
+      set(local_result TRUE)
+    else()
+      set(local_result FALSE)
+    endif()
+    message(STATUS "Checking whether I8MM is supported by the host system (via sysctl hw.optional.arm.FEAT_I8MM): ${local_result}")
+    set(${output} ${local_result} PARENT_SCOPE)
+endfunction(check_i8mm_support_on_darwin)
+
 # Checks whether the specified hardware capability is supported by the host
 # Linux system. This is implemented by checking auxiliary vector feature
 # provided by the Linux kernel.
@@ -115,9 +140,11 @@ function(check_emulator mlir_e2e_tests hwcap_spec emulator_exec)
 
   if(APPLE AND hwcap_spec STREQUAL "HWCAP2_SME")
     check_sme_support_on_darwin(emulator_not_required)
+  elseif(APPLE AND hwcap_spec STREQUAL "HWCAP2_I8MM")
+    check_i8mm_support_on_darwin(emulator_not_required)
   elseif(APPLE)
-    # No Darwin mapping for anything other than SME (yet); conservatively
-    # assume an emulator is required.
+    # No Darwin mapping for anything else (yet); conservatively assume an
+    # emulator is required.
     set(emulator_not_required FALSE)
   else()
     check_hwcap(${hwcap_spec} emulator_not_required)
diff --git a/mlir/test/Integration/Dialect/Vector/CPU/ArmNeon/vector-contract-i8mm.mlir b/mlir/test/Integration/Dialect/Vector/CPU/ArmNeon/vector-contract-i8mm.mlir
index f6012bbd3d0b2..dd96dbae2a09e 100644
--- a/mlir/test/Integration/Dialect/Vector/CPU/ArmNeon/vector-contract-i8mm.mlir
+++ b/mlir/test/Integration/Dialect/Vector/CPU/ArmNeon/vector-contract-i8mm.mlir
@@ -1,5 +1,3 @@
-// REQUIRES: arm-emulator
-
 // DEFINE: %{compile} = mlir-opt %s \
 // DEFINE:   --convert-vector-to-scf --convert-scf-to-cf  --convert-vector-to-llvm='enable-arm-neon enable-arm-i8mm' \
 // DEFINE:   --expand-strided-metadata --convert-to-llvm --finalize-memref-to-llvm  \

>From a973fcf42deeb474f9ce75642f5c312384449737 Mon Sep 17 00:00:00 2001
From: Federico Bruzzone <federico.bruzzone.i at gmail.com>
Date: Tue, 18 Aug 2026 01:29:00 +0200
Subject: [PATCH 2/3] Address comments

Signed-off-by: Federico Bruzzone <federico.bruzzone.i at gmail.com>
---
 .../Dialect/Vector/CPU/ArmNeon/vector-contract-i8mm.mlir        | 2 ++
 1 file changed, 2 insertions(+)

diff --git a/mlir/test/Integration/Dialect/Vector/CPU/ArmNeon/vector-contract-i8mm.mlir b/mlir/test/Integration/Dialect/Vector/CPU/ArmNeon/vector-contract-i8mm.mlir
index dd96dbae2a09e..b4dbc664f7ed9 100644
--- a/mlir/test/Integration/Dialect/Vector/CPU/ArmNeon/vector-contract-i8mm.mlir
+++ b/mlir/test/Integration/Dialect/Vector/CPU/ArmNeon/vector-contract-i8mm.mlir
@@ -1,3 +1,5 @@
+// REQUIRES: mlir_arm_i8mm_tests
+
 // DEFINE: %{compile} = mlir-opt %s \
 // DEFINE:   --convert-vector-to-scf --convert-scf-to-cf  --convert-vector-to-llvm='enable-arm-neon enable-arm-i8mm' \
 // DEFINE:   --expand-strided-metadata --convert-to-llvm --finalize-memref-to-llvm  \

>From 0226c8a1918ae201bb366d5d03ab4544b6d96a34 Mon Sep 17 00:00:00 2001
From: Federico Bruzzone <federico.bruzzone.i at gmail.com>
Date: Tue, 18 Aug 2026 20:04:34 +0200
Subject: [PATCH 3/3] Address comment

Signed-off-by: Federico Bruzzone <federico.bruzzone.i at gmail.com>
---
 mlir/cmake/modules/MLIRCheckHardwareFeatures.cmake | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/mlir/cmake/modules/MLIRCheckHardwareFeatures.cmake b/mlir/cmake/modules/MLIRCheckHardwareFeatures.cmake
index 00555c0b53ced..567fbdb9d93ee 100644
--- a/mlir/cmake/modules/MLIRCheckHardwareFeatures.cmake
+++ b/mlir/cmake/modules/MLIRCheckHardwareFeatures.cmake
@@ -121,8 +121,8 @@ endfunction(check_hwcap)
 #   emulator_exec
 # )
 #
-# mlir_e2e_tests  - MLIR CMake variables corresponding to the group of e2e tests
-#                   to check
+# mlir_e2e_tests  - Name of the MLIR CMake variable to gate on; also used to
+#                   name the flag in the error message below.
 # hwcap_spec      - HWCAP value to check. This should correspond to the hardware
 #                   capabilities required by the tests to be checked. Possible
 #                   values are defined in hwcap.h in the Linux kernel.