[mlir][sparse] Inline the definition of LLVM_ATTRIBUTE_WEAK

This library is supposed not to have a dependency on LLVM, and linking
LLVMSupport into it breaks its shared library setup.

mlir/lib/ExecutionEngine/Float16bits.cpp

@@ -12,7 +12,6 @@
 //===----------------------------------------------------------------------===//
 
 #include "mlir/ExecutionEngine/Float16bits.h"
-#include "llvm/Support/Compiler.h"
 
 namespace {
 
@@ -145,13 +144,23 @@ std::ostream &operator<<(std::ostream &os, const bf16 &d) {
 
 // Provide a float->bfloat conversion routine in case the runtime doesn't have
 // one.
-extern "C" uint16_t LLVM_ATTRIBUTE_WEAK __truncsfbf2(float f) {
+extern "C" uint16_t
+#if defined(__has_attribute) && __has_attribute(weak) &&                       \
+    !defined(__MINGW32__) && !defined(__CYGWIN__) && !defined(_WIN32)
+    __attribute__((__weak__))
+#endif
+    __truncsfbf2(float f) {
   return float2bfloat(f);
 }
 
 // Provide a double->bfloat conversion routine in case the runtime doesn't have
 // one.
-extern "C" uint16_t LLVM_ATTRIBUTE_WEAK __truncdfbf2(double d) {
+extern "C" uint16_t
+#if defined(__has_attribute) && __has_attribute(weak) &&                       \
+    !defined(__MINGW32__) && !defined(__CYGWIN__) && !defined(_WIN32)
+    __attribute__((__weak__))
+#endif
+    __truncdfbf2(double d) {
   // This does a double rounding step, but it's precise enough for our use
   // cases.
   return __truncsfbf2(static_cast<float>(d));

utils/bazel/llvm-project-overlay/mlir/BUILD.bazel

@@ -2226,14 +2226,14 @@ cc_library(
         "lib/Dialect/NVGPU/Transforms/PassDetail.h",
     ],
     hdrs = [
-        "include/mlir/Dialect/NVGPU/Transforms/Transforms.h",
         "include/mlir/Dialect/NVGPU/Passes.h",
+        "include/mlir/Dialect/NVGPU/Transforms/Transforms.h",
     ],
     includes = ["include"],
     deps = [
-        ":FuncDialect",
         ":AffineDialect",
         ":ArithmeticDialect",
+        ":FuncDialect",
         ":GPUDialect",
         ":IR",
         ":MemRefDialect",
@@ -6264,8 +6264,8 @@ cc_library(
         ":MemRefTransforms",
         ":NVGPUDialect",
         ":NVGPUPassIncGen",
-        ":NVGPUTransforms",
         ":NVGPUToNVVM",
+        ":NVGPUTransforms",
         ":NVVMDialect",
         ":OpenACCDialect",
         ":OpenMPDialect",
@@ -6409,9 +6409,6 @@ cc_library(
         "include/mlir/ExecutionEngine/SparseTensorUtils.h",
     ],
     includes = ["include"],
-    deps = [
-        "//llvm:Support",
-    ],
 )
 
 cc_library(