[mlir][emitc] Support 'emitc::LValueType' in 'emitc::VerbatimOp'

[EtoAndruwa]

This PR introduces support for emitc::LvalueType in emitc::VerbatimOp, providing a mechanism to reduce the number of operations required when working with verbatim operations whose arguments are of type emitc::LvalueType.

Before:

emitc.func @foo() {
  %a = "emitc.variable"() <{value = #emitc.opaque<"1">}> : () -> !emitc.lvalue<i32>
  %loaded_a = load %a : !emitc.lvalue<i32>
  emitc.verbatim "{} + {};" args %loaded_a, %loaded_a : i32, i32

  return
}

After:

emitc.func @bar() {
  %a = "emitc.variable"() <{value = #emitc.opaque<"1">}> : () -> !emitc.lvalue<i32>
  emitc.verbatim "{} + {};" args %a, %a : !emitc.lvalue<i32>, !emitc.lvalue<i32>

  return
}

You can now write something like this:

emitc.func @baz() {
  %a = "emitc.variable"() <{value = #emitc.opaque<"1">}> : () -> !emitc.lvalue<i32>
  emitc.verbatim "++{};" args %a : !emitc.lvalue<i32>

  return
}

[llvmbot]

@llvm/pr-subscribers-mlir

@llvm/pr-subscribers-mlir-emitc

Author: Andrey Timonin (EtoAndruwa)

Changes

This PR introduces support for emitc::LvalueType in emitc::VerbatimOp, providing a mechanism to reduce the number of operations required when working with verbatim operations whose arguments are of type emitc::LvalueType.

Before:

emitc.func @<!-- -->foo() {
  %a = "emitc.variable"() &lt;{value = #emitc.opaque&lt;"1"&gt;}&gt; : () -&gt; !emitc.lvalue&lt;i32&gt;
  %loaded_a = load %a : !emitc.lvalue&lt;i32&gt;
  emitc.verbatim "{} + {};" args %loaded_a, %loaded_a : i32, i32

  return
}

After:

emitc.func @<!-- -->bar() {
  %a = "emitc.variable"() &lt;{value = #emitc.opaque&lt;"1"&gt;}&gt; : () -&gt; !emitc.lvalue&lt;i32&gt;
  emitc.verbatim "{} + {};" args %a, %a : !emitc.lvalue&lt;i32&gt;, !emitc.lvalue&lt;i32&gt;

  return
}

You can now write something like this:

emitc.func @<!-- -->baz() {
  %a = "emitc.variable"() &lt;{value = #emitc.opaque&lt;"1"&gt;}&gt; : () -&gt; !emitc.lvalue&lt;i32&gt;
  emitc.verbatim "++{};" args %a : !emitc.lvalue&lt;i32&gt;

  return
}

---

Full diff: https://github.com/llvm/llvm-project/pull/144151.diff

2 Files Affected:

• (modified) mlir/include/mlir/Dialect/EmitC/IR/EmitC.td (+1-1)
• (modified) mlir/test/Dialect/EmitC/ops.mlir (+12-4)

diff --git a/mlir/include/mlir/Dialect/EmitC/IR/EmitC.td b/mlir/include/mlir/Dialect/EmitC/IR/EmitC.td
index d4aea52a0d485..e53d3e45875d5 100644
--- a/mlir/include/mlir/Dialect/EmitC/IR/EmitC.td
+++ b/mlir/include/mlir/Dialect/EmitC/IR/EmitC.td
@@ -1304,7 +1304,7 @@ def EmitC_VerbatimOp : EmitC_Op<"verbatim"> {
     FailureOr<SmallVector<::mlir::emitc::ReplacementItem>> parseFormatString();
   }];
 
-  let arguments = (ins StrAttr:$value, Variadic<EmitCType>:$fmtArgs);
+  let arguments = (ins StrAttr:$value, Variadic<AnyTypeOf<[EmitCType, EmitC_LValueType]>>:$fmtArgs);
 
   let builders = [OpBuilder<(ins "::mlir::StringAttr":$value),
                             [{ build($_builder, $_state, value, {}); }]>];
diff --git a/mlir/test/Dialect/EmitC/ops.mlir b/mlir/test/Dialect/EmitC/ops.mlir
index 36d12e763afc7..2ca7c4bc3bbb5 100644
--- a/mlir/test/Dialect/EmitC/ops.mlir
+++ b/mlir/test/Dialect/EmitC/ops.mlir
@@ -246,12 +246,20 @@ emitc.verbatim "typedef float f32;"
 // The value is not interpreted as format string if there are no operands.
 emitc.verbatim "{} {  }"
 
-func.func @test_verbatim(%arg0 : !emitc.ptr<i32>, %arg1 : i32) {
+func.func @test_verbatim(%arg0 : !emitc.ptr<i32>, %arg1 : i32, %arg3: !emitc.array<3x!emitc.ptr<i32>>) {
+  %a = "emitc.variable"() <{value = #emitc.opaque<"1">}> : () -> !emitc.lvalue<i32>
+
+  // Check that the lvalue type can be used by verbatim.
+  emitc.verbatim "++{};" args %a : !emitc.lvalue<i32>
+
+  // Check that the array type can be used by verbatim.
+  emitc.verbatim "*{}[0] = 1;" args %arg3 : !emitc.array<3x!emitc.ptr<i32>>
+
   emitc.verbatim "{} + {};" args %arg0, %arg1 : !emitc.ptr<i32>, i32
 
-  // Check there is no ambiguity whether %a is the argument to the emitc.verbatim op.
-  emitc.verbatim "a"
-  %a = "emitc.constant"(){value = 42 : i32} : () -> i32
+  // Check there is no ambiguity whether %b is the argument to the emitc.verbatim op.
+  emitc.verbatim "b"
+  %b = "emitc.constant"(){value = 42 : i32} : () -> i32
 
   return
 }

[marbre]

@simon-camp do you see any problem with using an LValue in the VerbatimOp I might miss?

[mgehre-amd]

Looks good to me.

[simon-camp]

LGTM, besides the Argument Name.

[marbre]

Build failures seem unrelated.

[EtoAndruwa]

Build failures seem unrelated.

Also noticed this.

Flang's test fails:

Failed Tests (1):
  Flang :: Profile/gcc-flag-compatibility.f90

[EtoAndruwa]

I don't have rights to merge, so someone should merge this. Thanks!