Skip to content

Instantly share code, notes, and snippets.

View bjacob's full-sized avatar

Benoit Jacob bjacob

93 followers · 0 following
View GitHub Profile
@bjacob
bjacob / proposal.md
Created January 26, 2026 14:45

Hello,

1. The preexisting potential undefined behavior in FP conversions.

There is an edge case in the specification potentially allowing for value-dependent undefined behavior (henceforth UB) in floating-point conversions:

7.3.10 [conv.double] #2 says:

If the source value can be exactly represented in the destination type, the result of the conversion is that exact representation. If the source value is between two adjacent destination values, the result of the conversion is an implementation-defined choice of either of those values. Otherwise, the behavior is undefined.

@bjacob
bjacob / proposal.txt
Created January 26, 2026 14:43
Hello,
1. The preexisting potential undefined behavior in FP conversions.
There is an edge case in the specification potentially allowing for value-dependent undefined behavior (henceforth UB) in floating-point conversions:
7.3.10 [conv.double] #2 says:
If the source value can be exactly represented in the destination type, the result of the conversion is that exact representation. If the source value is between two adjacent destination values, the result of the conversion is an implementation-defined choice of either of those values. Otherwise, the behavior is undefined.
@bjacob
bjacob / a.diff
Created January 22, 2026 23:50
diff --git a/tmp/log-good.mlir b/tmp/log-bad.mlir
index 0408554..f00f377 100644
--- a/tmp/log-good.mlir
+++ b/tmp/log-bad.mlir
@@ -400,7 +400,7 @@ module {
%11 = iree_tensor_ext.dispatch.tensor.load %8, offsets = [0, 0, 0, 0], sizes = [48, 768, 16, 1], strides = [1, 1, 1, 1] : !iree_tensor_ext.dispatch.tensor<readonly:tensor<48x768x16x1xf16>> -> tensor<48x768x16x1xf16>
%12 = tensor.empty() : tensor<4x48x16x16xf32>
%13 = linalg.fill {lowering_config = #iree_cpu.lowering_config<vector_common_parallel = [1, 1, 16, 16]>} ins(%cst : f32) outs(%12 : tensor<4x48x16x16xf32>) -> tensor<4x48x16x16xf32>
- %14 = linalg.mmt4d {lowering_config = #iree_cpu.lowering_config<distribution = [4, 4, 0, 0, 0, 0], vector_common_parallel = [1, 1, 0, 16, 16, 0], vector_reduction = [0, 0, 1, 0, 0, 1]>} ins(%10, %11 : tensor<4x768x16x1xf16>, tensor<48x768x16x1xf16>) outs(%13 : tensor<4x48x16x16xf32>) -> tensor<4x48x16x16xf32>
+ %14 = linalg.mmt4d {lowering_config = #iree_cpu.lowering_config<distribution = [4, 48, 0
@bjacob
bjacob / log.txt
Created January 22, 2026 21:35
---------------------------- live log sessionstart -----------------------------
INFO conftest:conftest.py:38 Pytest quality test session is starting
============================= test session starts ==============================
platform linux -- Python 3.12.3, pytest-8.0.0, pluggy-1.6.0
rootdir: /home/ossci/iree-test-suites/sharktank_models
configfile: pytest.ini
plugins: anyio-4.11.0, xdist-3.5.0, timeout-2.4.0, subtests-0.15.0, metadata-3.1.1, cov-7.0.0, asyncio-0.23.8, html-4.1.1, retry-1.7.0, reportlog-1.0.0, check-2.6.0
timeout: 600.0s
timeout method: signal
@bjacob
bjacob / gist:f2da084dd681911d32059df82b44c8e5
Created December 18, 2025 15:25
FAILED: tests/e2e/math/math_ops_llvm-cpu_math_ops_llvm-cpu.mlir_module.vmfb /tmp/xx/iree-build/tests/e2e/math/math_ops_llvm-cpu_math_ops_llvm-cpu.mlir_module.vmfb
cd /tmp/xx/iree-build/tests/e2e/math && /tmp/xx/iree-build/tools/iree-compile --output-format=vm-bytecode --mlir-print-op-on-diagnostic=false --iree-hal-target-backends=llvm-cpu --iree-llvmcpu-target-cpu=generic /tmp/xx/iree-build/tests/e2e/math/math_ops_llvm-cpu.mlir -o math_ops_llvm-cpu_math_ops_llvm-cpu.mlir_module.vmfb --iree-hal-executable-object-search-path=\"/tmp/xx/iree-build\" --iree-llvmcpu-embedded-linker-path=\"/tmp/xx/iree-build/llvm-project/bin/lld\" --iree-llvmcpu-wasm-linker-path=\"/tmp/xx/iree-build/llvm-project/bin/lld\"
lld: error: undefined symbol: fma
>>> referenced by math_ops_llvm-cpu.mlir:29
>>> /tmp/math_ops_llvm_cpu_linked-cb60c2.o:(_test_acos_f16_dispatch_0_elementwise_9_f16)
>>> referenced by math_ops_llvm-cpu.mlir:29
>>> /tmp/math_ops_llvm_cpu_linked-cb60c2.o:(_test_acos_f16_dispatch_0_elemen
@bjacob
bjacob / a.diff
Created December 16, 2025 20:55
diff --git a/compiler/src/iree/compiler/API/BUILD.bazel b/compiler/src/iree/compiler/API/BUILD.bazel
index 543a088fba..43ff10395d 100644
--- a/compiler/src/iree/compiler/API/BUILD.bazel
+++ b/compiler/src/iree/compiler/API/BUILD.bazel
@@ -38,6 +38,7 @@ iree_compiler_cc_library(
"//compiler/src/iree/compiler/API/Internal:IREEReduceToolEntryPoint",
"//compiler/src/iree/compiler/API/Internal:LLDToolEntryPoint",
"//llvm-external-projects/iree-dialects:CAPI",
+ "@llvm-project//mlir:CAPIAMDGPU",
"@llvm-project//mlir:CAPIDebug",
@bjacob
bjacob / gist:f4fe45961d1b70dd713260e08f31b4ae
Created December 7, 2025 14:20
➜ iree-build ninja iree-opt && tools/iree-opt '--pass-pipeline=builtin.module(func.func(iree-codegen-materialize-device-encoding))' /tmp/xx/iree/compiler/plugins/target/ROCM/test/materialize_encoding_ukernel_gfx942.mlir
[0/2] Re-checking globbed directories...
[4/4] Linking CXX executable tools/iree-opt
=================================================================
==118841==ERROR: AddressSanitizer: heap-use-after-free on address 0x7cd8cc303aec at pc 0x7ff8e297eb6d bp 0x7bf8c725b8f0 sp 0x7bf8c725b8e8
READ of size 4 at 0x7cd8cc303aec thread T5
#0 0x7ff8e297eb6c in mlir::Operation::getPropertiesStorageSize() const /tmp/xx/iree/third_party/llvm-project/mlir/include/mlir/IR/Operation.h:897:18
#1 0x7ff8e297eb6c in mlir::Operation::getAttr(llvm::StringRef) /tmp/xx/iree/third_party/llvm-project/mlir/include/mlir/IR/Operation.h:542:9
#2 0x7ff8e297eb6c in mlir::iree_compiler::IREE::ROCM::TensorUKernelProviderAttr::getDataLayoutForUKernel(mlir::Attribute, mlir::DictionaryAttr) const /tmp/xx/iree/compil
@bjacob
bjacob / gist:b7400ba1d6ab56274bd44a3fe3b5c105
Created December 7, 2025 03:47
(gdb) thread apply all bt
Thread 7 (Thread 0x7ffff520a6c0 (LWP 1109500) "llvm-worker-5"):
#0 0x00007ffff7aafd71 in __futex_abstimed_wait_common64 (private=32767, cancel=true, abstime=0x0, op=393, expected=0, futex_word=0x555561966fc4) at ./nptl/futex-internal.c:57
#1 __futex_abstimed_wait_common (cancel=true, private=32767, abstime=0x0, clockid=0, expected=0, futex_word=0x555561966fc4) at ./nptl/futex-internal.c:87
#2 __GI___futex_abstimed_wait_cancelable64 (futex_word=futex_word@entry=0x555561966fc4, expected=expected@entry=0, clockid=clockid@entry=0, abstime=abstime@entry=0x0, private=private@entry=0) at ./nptl/futex-internal.c:139
#3 0x00007ffff7ab27ed in __pthread_cond_wait_common (abstime=0x0, clockid=0, mutex=0x555561966f70, cond=0x555561966f98) at ./nptl/pthread_cond_wait.c:503
#4 ___pthread_cond_wait (cond=0x555561966f98, mutex=0x555561966f70) at ./nptl/pthread_cond_wait.c:627
#5 0x00005555613da316 in llvm::StdThreadPool::processTasks(llvm::ThreadPoolTaskGroup*) ()
#6 0x00005555613da777 in voi
@bjacob
bjacob / gist:4a744677f5c396a2c5ea185ef1b86ad3
Created December 5, 2025 19:51
(gdb) thread apply all bt
Thread 7 (Thread 0x7fffc37fe6c0 (LWP 1644017) "llvm-worker-5"):
#0 0x00007fffd2825d71 in __futex_abstimed_wait_common64 (private=32767, cancel=true, abstime=0x0, op=393, expected=0, futex_word=0x555555f75a20) at ./nptl/futex-internal.c:57
#1 __futex_abstimed_wait_common (cancel=true, private=32767, abstime=0x0, clockid=0, expected=0, futex_word=0x555555f75a20) at ./nptl/futex-internal.c:87
#2 __GI___futex_abstimed_wait_cancelable64 (futex_word=futex_word@entry=0x555555f75a20, expected=expected@entry=0, clockid=clockid@entry=0, abstime=abstime@entry=0x0, private=private@entry=0) at ./nptl/futex-internal.c:139
#3 0x00007fffd28287ed in __pthread_cond_wait_common (abstime=0x0, clockid=0, mutex=0x555555f759d0, cond=0x555555f759f8) at ./nptl/pthread_cond_wait.c:503
#4 ___pthread_cond_wait (cond=0x555555f759f8, mutex=0x555555f759d0) at ./nptl/pthread_cond_wait.c:627
#5 0x00007fffe35b15cb in std::condition_variable::wait<llvm::StdThreadPool::processTasks(llvm::ThreadPoolTaskGroup*)::$
@bjacob
bjacob / a.diff
Created December 5, 2025 17:42
diff --git a/runtime/src/iree/vm/native_module_packing.h b/runtime/src/iree/vm/native_module_packing.h
index 705b68528a..be0ee5047e 100644
--- a/runtime/src/iree/vm/native_module_packing.h
+++ b/runtime/src/iree/vm/native_module_packing.h
@@ -8,6 +8,7 @@
#define IREE_VM_MODULE_ABI_PACKING_H_
#include <memory>
+#include <numeric>
#include <tuple>