[llvm-branch-commits] [mlir] 70b841a - [mlir] Adds argument attributes for using LLVM's sret and byval attributes

[Eric Schweitz via llvm-branch-commits]

Author: Eric Schweitz
Date: 2021-01-07T12:52:14-08:00
New Revision: 70b841ac317765c5c504334f7a22ac085f14ac2d

URL: https://github.com/llvm/llvm-project/commit/70b841ac317765c5c504334f7a22ac085f14ac2d
DIFF: https://github.com/llvm/llvm-project/commit/70b841ac317765c5c504334f7a22ac085f14ac2d.diff

LOG: [mlir] Adds argument attributes for using LLVM's sret and byval attributes
to the conversion of LLVM IR dialect. These attributes are used in FIR to
support the lowering of Fortran using target-specific calling conventions.

Add roundtrip tests.

Add changes per review comments/concerns.

Reviewed By: ftynse

Differential Revision: https://reviews.llvm.org/D94052

Added: 
    

Modified: 
    mlir/lib/Target/LLVMIR/ModuleTranslation.cpp
    mlir/test/Dialect/LLVMIR/func.mlir
    mlir/test/Target/llvmir-invalid.mlir

Removed: 
    


################################################################################
diff  --git a/mlir/lib/Target/LLVMIR/ModuleTranslation.cpp b/mlir/lib/Target/LLVMIR/ModuleTranslation.cpp
index 7700867bb461..492025ba37b4 100644
--- a/mlir/lib/Target/LLVMIR/ModuleTranslation.cpp
+++ b/mlir/lib/Target/LLVMIR/ModuleTranslation.cpp
@@ -1102,6 +1102,22 @@ LogicalResult ModuleTranslation::convertOneFunction(LLVMFuncOp func) {
           llvm::AttrBuilder().addAlignmentAttr(llvm::Align(attr.getInt())));
     }
 
+    if (auto attr = func.getArgAttrOfType<UnitAttr>(argIdx, "llvm.sret")) {
+      auto argTy = mlirArg.getType();
+      if (!argTy.isa<LLVM::LLVMPointerType>())
+        return func.emitError(
+            "llvm.sret attribute attached to LLVM non-pointer argument");
+      llvmArg.addAttr(llvm::Attribute::AttrKind::StructRet);
+    }
+
+    if (auto attr = func.getArgAttrOfType<UnitAttr>(argIdx, "llvm.byval")) {
+      auto argTy = mlirArg.getType();
+      if (!argTy.isa<LLVM::LLVMPointerType>())
+        return func.emitError(
+            "llvm.byval attribute attached to LLVM non-pointer argument");
+      llvmArg.addAttr(llvm::Attribute::AttrKind::ByVal);
+    }
+
     valueMapping[mlirArg] = &llvmArg;
     argIdx++;
   }

diff  --git a/mlir/test/Dialect/LLVMIR/func.mlir b/mlir/test/Dialect/LLVMIR/func.mlir
index 72e117d57a91..d9d7e17a9b50 100644
--- a/mlir/test/Dialect/LLVMIR/func.mlir
+++ b/mlir/test/Dialect/LLVMIR/func.mlir
@@ -87,6 +87,16 @@ module {
     llvm.return
   }
 
+  // CHECK: llvm.func @byvalattr(%{{.*}}: !llvm.ptr<i32> {llvm.byval})
+  llvm.func @byvalattr(%arg0: !llvm.ptr<i32> {llvm.byval}) {
+    llvm.return
+  }
+
+  // CHECK: llvm.func @sretattr(%{{.*}}: !llvm.ptr<i32> {llvm.sret})
+  llvm.func @sretattr(%arg0: !llvm.ptr<i32> {llvm.sret}) {
+    llvm.return
+  }
+
   // CHECK: llvm.func @variadic(...)
   llvm.func @variadic(...)
 

diff  --git a/mlir/test/Target/llvmir-invalid.mlir b/mlir/test/Target/llvmir-invalid.mlir
index 14117594e2f8..fcd98ef4b143 100644
--- a/mlir/test/Target/llvmir-invalid.mlir
+++ b/mlir/test/Target/llvmir-invalid.mlir
@@ -14,6 +14,19 @@ llvm.func @invalid_noalias(%arg0 : !llvm.float {llvm.noalias = true}) -> !llvm.f
 
 // -----
 
+// expected-error @+1 {{llvm.sret attribute attached to LLVM non-pointer argument}}
+llvm.func @invalid_noalias(%arg0 : !llvm.float {llvm.sret}) -> !llvm.float {
+  llvm.return %arg0 : !llvm.float
+}
+// -----
+
+// expected-error @+1 {{llvm.byval attribute attached to LLVM non-pointer argument}}
+llvm.func @invalid_noalias(%arg0 : !llvm.float {llvm.byval}) -> !llvm.float {
+  llvm.return %arg0 : !llvm.float
+}
+
+// -----
+
 // expected-error @+1 {{llvm.align attribute attached to LLVM non-pointer argument}}
 llvm.func @invalid_align(%arg0 : !llvm.float {llvm.align = 4}) -> !llvm.float {
   llvm.return %arg0 : !llvm.float