Skip to content

[MLIR][LivenessAnalysis] Treat a public function as an external #160648

New issue

Have a question about this project? Sign up for a free GitHub account to open an issue and contact its maintainers and the community.

Sign up for GitHub

By clicking “Sign up for GitHub”, you agree to our terms of service and privacy statement. We’ll occasionally send you account related emails.

Already on GitHub? Sign in to your account

Closed
navyxliu wants to merge 6 commits into from
Closed

[MLIR][LivenessAnalysis] Treat a public function as an external #160648

Show file tree
Hide file tree
Changes from 3 commits
Commits
Show all changes
6 commits
Select commit Hold shift + click to select a range
d54a007
[MLIR][LivenessAnalysis] Treat a public function as an external
navyxliu Sep 25, 2025
ed25cb7
Fix formatter error.
navyxliu Sep 25, 2025
153e6e6
Update the comment and also add lit test.
navyxliu Sep 26, 2025
9e35848
Update the comment.
navyxliu Sep 26, 2025
c166b1f
Simplify lit test. use more descriptive name.
navyxliu Sep 26, 2025
5830289
Make the lit test minimal.
navyxliu Sep 26, 2025
File filter

Filter by extension

Filter by extension
Conversations
Failed to load comments.
Loading
Jump to
Jump to file
Failed to load files.
Loading
Diff view
Diff view
12 changes: 10 additions & 2 deletions mlir/lib/Analysis/DataFlow/SparseAnalysis.cpp
View file
Open in desktop
Original file line number Diff line number Diff line change
Expand Up @@ -17,6 +17,7 @@
#include "mlir/IR/ValueRange.h"
#include "mlir/Interfaces/CallInterfaces.h"
#include "mlir/Interfaces/ControlFlowInterfaces.h"
#include "mlir/Interfaces/FunctionInterfaces.h"
#include "mlir/Support/LLVM.h"
#include "llvm/ADT/STLExtras.h"
#include "llvm/Support/DebugLog.h"
Expand Down Expand Up @@ -505,12 +506,19 @@ AbstractSparseBackwardDataFlowAnalysis::visitOperation(Operation *op) {
// If the call invokes an external function (or a function treated as
// external due to config), defer to the corresponding extension hook.
// By default, it just does `visitCallOperand` for all operands.
//
// If callable is a public function, the signature is immutable.
// We need to be conservative and consider all arguments Live.
OperandRange argOperands = call.getArgOperands();
MutableArrayRef<OpOperand> argOpOperands =
operandsToOpOperands(argOperands);
Region *region = callable.getCallableRegion();
if (!region || region->empty() ||
!getSolverConfig().isInterprocedural()) {
auto isPublicFunction = [&]() {
auto funcOp = dyn_cast<FunctionOpInterface>(callableOp);
return funcOp && funcOp.isPublic();
};
if (!getSolverConfig().isInterprocedural() || !region ||
region->empty() || isPublicFunction()) {
visitExternalCallImpl(call, operandLattices, resultLattices);
return success();
}
Expand Down
17 changes: 17 additions & 0 deletions mlir/test/Transforms/remove-dead-values.mlir
View file
Open in desktop
Original file line number Diff line number Diff line change
Expand Up @@ -569,6 +569,23 @@ module @return_void_with_unused_argument {
call @fn_return_void_with_unused_argument(%arg0, %unused) : (i32, memref<4xi32>) -> ()
return %unused : memref<4xi32>
}
// the function is immutable because it is public.
func.func public @immutable_fn_return_void_with_unused_argument(%arg0: i32, %unused: i32) -> () {
%sum = arith.addi %arg0, %arg0 : i32
%c0 = arith.constant 0 : index
%buf = memref.alloc() : memref<1xi32>
memref.store %sum, %buf[%c0] : memref<1xi32>
return
}
// CHECK-LABEL: func.func @main2
// CHECK-SAME: (%[[ARG0_MAIN:.*]]: i32)
// CHECK: %[[UNUSED:.*]] = arith.constant 0 : i32
// CHECK: call @immutable_fn_return_void_with_unused_argument(%[[ARG0_MAIN]], %[[UNUSED]]) : (i32, i32) -> ()
func.func @main2(%arg0: i32) -> () {
%zero = arith.constant 0 : i32
call @immutable_fn_return_void_with_unused_argument(%arg0, %zero) : (i32, i32) -> ()
return
}
}

// -----
Expand Down