[flang-commits] [flang] 6b44274 - [Flang][MLIR] Alter Fir.GlobalOp to print and lower external attributes

[Andrew Gozillon via flang-commits]

Author: Andrew Gozillon
Date: 2023-04-20T07:06:05-05:00
New Revision: 6b44274d8309c4e8daeecdcc6a14259015a3923f

URL: https://github.com/llvm/llvm-project/commit/6b44274d8309c4e8daeecdcc6a14259015a3923f
DIFF: https://github.com/llvm/llvm-project/commit/6b44274d8309c4e8daeecdcc6a14259015a3923f.diff

LOG: [Flang][MLIR] Alter Fir.GlobalOp to print and lower external attributes

Fir.GlobalOp's currently do not respect attributes that
are applied to them, this change will do two things:

- Allow lowering of arbitrary attributes applied to
Fir.GlobalOp's to LLVMGlobalOp's during CodeGen
- Allow printing and parsing of arbitrarily applied attributes

This allows applying other dialects attributes (or other
fir attributes) to fir.GlobalOps on the fly and have them
exist in the resulting LLVM dialect IR or FIR IR.

Reviewer: jeanPerier

Differential Revision: https://reviews.llvm.org/D148352

Added: 
    flang/test/Fir/global-attributes.fir

Modified: 
    flang/lib/Optimizer/CodeGen/CodeGen.cpp
    flang/lib/Optimizer/Dialect/FIROps.cpp

Removed: 
    


################################################################################
diff  --git a/flang/lib/Optimizer/CodeGen/CodeGen.cpp b/flang/lib/Optimizer/CodeGen/CodeGen.cpp
index 2e461d704cbf1..72f02cb425299 100644
--- a/flang/lib/Optimizer/CodeGen/CodeGen.cpp
+++ b/flang/lib/Optimizer/CodeGen/CodeGen.cpp
@@ -2855,6 +2855,16 @@ struct GlobalOpConversion : public FIROpConversion<fir::GlobalOp> {
     auto isConst = global.getConstant().has_value();
     auto g = rewriter.create<mlir::LLVM::GlobalOp>(
         loc, tyAttr, isConst, linkage, global.getSymName(), initAttr);
+
+    // Apply all non-Fir::GlobalOp attributes to the LLVM::GlobalOp, preserving
+    // them; whilst taking care not to apply attributes that are lowered in
+    // other ways.
+    llvm::SmallDenseSet<llvm::StringRef> elidedAttrsSet(
+        global.getAttributeNames().begin(), global.getAttributeNames().end());
+    for (auto &attr : global->getAttrs())
+      if (!elidedAttrsSet.contains(attr.getName().strref()))
+        g->setAttr(attr.getName(), attr.getValue());
+
     auto &gr = g.getInitializerRegion();
     rewriter.inlineRegionBefore(global.getRegion(), gr, gr.end());
     if (!gr.empty()) {

diff  --git a/flang/lib/Optimizer/Dialect/FIROps.cpp b/flang/lib/Optimizer/Dialect/FIROps.cpp
index 3188a166ef0cd..3e158183d0138 100644
--- a/flang/lib/Optimizer/Dialect/FIROps.cpp
+++ b/flang/lib/Optimizer/Dialect/FIROps.cpp
@@ -1308,6 +1308,9 @@ mlir::ParseResult fir::GlobalOp::parse(mlir::OpAsmParser &parser,
     simpleInitializer = true;
   }
 
+  if (parser.parseOptionalAttrDict(result.attributes))
+    return mlir::failure();
+
   if (succeeded(parser.parseOptionalKeyword("constant"))) {
     // if "constant" keyword then mark this as a constant, not a variable
     result.addAttribute("constant", builder.getUnitAttr());
@@ -1342,6 +1345,7 @@ void fir::GlobalOp::print(mlir::OpAsmPrinter &p) {
   p.printAttributeWithoutType(getSymrefAttr());
   if (auto val = getValueOrNull())
     p << '(' << val << ')';
+  p.printOptionalAttrDict((*this)->getAttrs(), (*this).getAttributeNames());
   if (getOperation()->getAttr(fir::GlobalOp::getConstantAttrNameStr()))
     p << " constant";
   if (getOperation()->getAttr(getTargetAttrName()))

diff  --git a/flang/test/Fir/global-attributes.fir b/flang/test/Fir/global-attributes.fir
new file mode 100644
index 0000000000000..24442d671504f
--- /dev/null
+++ b/flang/test/Fir/global-attributes.fir
@@ -0,0 +1,17 @@
+// RUN: fir-opt --fir-to-llvm-ir %s | FileCheck %s
+// RUN: tco --fir-to-llvm-ir %s | FileCheck %s
+// RUN: fir-opt %s | FileCheck %s --check-prefix=READ-OUT
+// RUN: tco --emit-fir %s | FileCheck %s --check-prefix=READ-OUT
+
+// CHECK: llvm.mlir.global external @_QMtest_0Edata_int() {{{.*}}test = "string_attribute_maintained"{{.*}}} : i32 {
+// CHECK: [[CST0:%.*]] = llvm.mlir.constant(10 : i32) : i32
+// CHECK: llvm.return [[CST0]] : i32
+// CHECK: }
+// READ-OUT: fir.global @_QMtest_0Edata_int {test = "string_attribute_maintained"} : i32 {
+// READ-OUT: %c10_i32 = arith.constant 10 : i32
+// READ-OUT: fir.has_value %c10_i32 : i32
+// READ-OUT: }
+fir.global @_QMtest_0Edata_int {test = "string_attribute_maintained"} : i32 {
+  %c10_i32 = arith.constant 10 : i32
+  fir.has_value %c10_i32 : i32
+}