Fault when lowering mlir dialect to llvm and compiled it on ARM

MLIR
1

I converted affine & std dialect to llvm dialect, then translated to llvm ir. And then use llc and clang to build the object file. But I got segmentation error when I ran the executable on ARM.
Affine & std Dialect:

module  {
  func @laplace(%arg0: memref<72x18x16xf64>, %arg1: memref<72x18x16xf64>) {
    %0 = memref.alloc() : memref<72x18x16xf64>
    affine.for %arg2 = 1 to 71 {
      affine.for %arg3 = 1 to 17 {
        affine.for %arg4 = 0 to 16 {
          %cst = constant -4.000000e+00 : f64
          affine.store %cst, %arg1[%arg2, %arg3, %arg4] : memref<72x18x16xf64>
        }
      }
    }
    return
  }
}

then I added these passes:

  LLVMTypeConverter typeConverter(&getContext());

  RewritePatternSet patterns(&getContext());
  populateAffineToStdConversionPatterns(patterns);
  populateLoopToStdConversionPatterns(patterns);
  populateMemRefToLLVMConversionPatterns(typeConverter, patterns);
  populateStdToLLVMConversionPatterns(typeConverter, patterns);

and got the llvm dialect:

module  {
  llvm.func @malloc(i64) -> !llvm.ptr<i8>
  llvm.func @laplace(%arg0: !llvm.ptr<f64>, %arg1: !llvm.ptr<f64>, %arg2: i64, %arg3: i64, %arg4: i64, %arg5: i64, %arg6: i64, %arg7: i64, %arg8: i64, %arg9: !llvm.ptr<f64>, %arg10: !llvm.ptr<f64>, %arg11: i64, %arg12: i64, %arg13: i64, %arg14: i64, %arg15: i64, %arg16: i64, %arg17: i64) {
    %0 = llvm.mlir.undef : !llvm.struct<(ptr<f64>, ptr<f64>, i64, array<3 x i64>, array<3 x i64>)>
    %1 = llvm.insertvalue %arg0, %0[0] : !llvm.struct<(ptr<f64>, ptr<f64>, i64, array<3 x i64>, array<3 x i64>)>
    %2 = llvm.insertvalue %arg1, %1[1] : !llvm.struct<(ptr<f64>, ptr<f64>, i64, array<3 x i64>, array<3 x i64>)>
    %3 = llvm.insertvalue %arg2, %2[2] : !llvm.struct<(ptr<f64>, ptr<f64>, i64, array<3 x i64>, array<3 x i64>)>
    %4 = llvm.insertvalue %arg3, %3[3, 0] : !llvm.struct<(ptr<f64>, ptr<f64>, i64, array<3 x i64>, array<3 x i64>)>
    %5 = llvm.insertvalue %arg6, %4[4, 0] : !llvm.struct<(ptr<f64>, ptr<f64>, i64, array<3 x i64>, array<3 x i64>)>
    %6 = llvm.insertvalue %arg4, %5[3, 1] : !llvm.struct<(ptr<f64>, ptr<f64>, i64, array<3 x i64>, array<3 x i64>)>
    %7 = llvm.insertvalue %arg7, %6[4, 1] : !llvm.struct<(ptr<f64>, ptr<f64>, i64, array<3 x i64>, array<3 x i64>)>
    %8 = llvm.insertvalue %arg5, %7[3, 2] : !llvm.struct<(ptr<f64>, ptr<f64>, i64, array<3 x i64>, array<3 x i64>)>
    %9 = llvm.insertvalue %arg8, %8[4, 2] : !llvm.struct<(ptr<f64>, ptr<f64>, i64, array<3 x i64>, array<3 x i64>)>
    %10 = llvm.mlir.undef : !llvm.struct<(ptr<f64>, ptr<f64>, i64, array<3 x i64>, array<3 x i64>)>
    %11 = llvm.insertvalue %arg9, %10[0] : !llvm.struct<(ptr<f64>, ptr<f64>, i64, array<3 x i64>, array<3 x i64>)>
    %12 = llvm.insertvalue %arg10, %11[1] : !llvm.struct<(ptr<f64>, ptr<f64>, i64, array<3 x i64>, array<3 x i64>)>
    %13 = llvm.insertvalue %arg11, %12[2] : !llvm.struct<(ptr<f64>, ptr<f64>, i64, array<3 x i64>, array<3 x i64>)>
    %14 = llvm.insertvalue %arg12, %13[3, 0] : !llvm.struct<(ptr<f64>, ptr<f64>, i64, array<3 x i64>, array<3 x i64>)>
    %15 = llvm.insertvalue %arg15, %14[4, 0] : !llvm.struct<(ptr<f64>, ptr<f64>, i64, array<3 x i64>, array<3 x i64>)>
    %16 = llvm.insertvalue %arg13, %15[3, 1] : !llvm.struct<(ptr<f64>, ptr<f64>, i64, array<3 x i64>, array<3 x i64>)>
    %17 = llvm.insertvalue %arg16, %16[4, 1] : !llvm.struct<(ptr<f64>, ptr<f64>, i64, array<3 x i64>, array<3 x i64>)>
    %18 = llvm.insertvalue %arg14, %17[3, 2] : !llvm.struct<(ptr<f64>, ptr<f64>, i64, array<3 x i64>, array<3 x i64>)>
    %19 = llvm.insertvalue %arg17, %18[4, 2] : !llvm.struct<(ptr<f64>, ptr<f64>, i64, array<3 x i64>, array<3 x i64>)>
    %20 = llvm.mlir.constant(72 : index) : i64
    %21 = llvm.mlir.constant(18 : index) : i64
    %22 = llvm.mlir.constant(16 : index) : i64
    %23 = llvm.mlir.constant(1 : index) : i64
    %24 = llvm.mlir.constant(288 : index) : i64
    %25 = llvm.mlir.constant(20736 : index) : i64
    %26 = llvm.mlir.null : !llvm.ptr<f64>
    %27 = llvm.getelementptr %26[%25] : (!llvm.ptr<f64>, i64) -> !llvm.ptr<f64>
    %28 = llvm.ptrtoint %27 : !llvm.ptr<f64> to i64
    %29 = llvm.call @malloc(%28) : (i64) -> !llvm.ptr<i8>
    %30 = llvm.bitcast %29 : !llvm.ptr<i8> to !llvm.ptr<f64>
    %31 = llvm.mlir.undef : !llvm.struct<(ptr<f64>, ptr<f64>, i64, array<3 x i64>, array<3 x i64>)>
    %32 = llvm.insertvalue %30, %31[0] : !llvm.struct<(ptr<f64>, ptr<f64>, i64, array<3 x i64>, array<3 x i64>)>
    %33 = llvm.insertvalue %30, %32[1] : !llvm.struct<(ptr<f64>, ptr<f64>, i64, array<3 x i64>, array<3 x i64>)>
    %34 = llvm.mlir.constant(0 : index) : i64
    %35 = llvm.insertvalue %34, %33[2] : !llvm.struct<(ptr<f64>, ptr<f64>, i64, array<3 x i64>, array<3 x i64>)>
    %36 = llvm.insertvalue %20, %35[3, 0] : !llvm.struct<(ptr<f64>, ptr<f64>, i64, array<3 x i64>, array<3 x i64>)>
    %37 = llvm.insertvalue %21, %36[3, 1] : !llvm.struct<(ptr<f64>, ptr<f64>, i64, array<3 x i64>, array<3 x i64>)>
    %38 = llvm.insertvalue %22, %37[3, 2] : !llvm.struct<(ptr<f64>, ptr<f64>, i64, array<3 x i64>, array<3 x i64>)>
    %39 = llvm.insertvalue %24, %38[4, 0] : !llvm.struct<(ptr<f64>, ptr<f64>, i64, array<3 x i64>, array<3 x i64>)>
    %40 = llvm.insertvalue %22, %39[4, 1] : !llvm.struct<(ptr<f64>, ptr<f64>, i64, array<3 x i64>, array<3 x i64>)>
    %41 = llvm.insertvalue %23, %40[4, 2] : !llvm.struct<(ptr<f64>, ptr<f64>, i64, array<3 x i64>, array<3 x i64>)>
    %42 = llvm.mlir.constant(1 : index) : i64
    %43 = llvm.mlir.constant(71 : index) : i64
    %44 = llvm.mlir.constant(1 : index) : i64
    llvm.br ^bb1(%42 : i64)
  ^bb1(%45: i64):  // 2 preds: ^bb0, ^bb8
    %46 = llvm.icmp "slt" %45, %43 : i64
    llvm.cond_br %46, ^bb2, ^bb9
  ^bb2:  // pred: ^bb1
    %47 = llvm.mlir.constant(1 : index) : i64
    %48 = llvm.mlir.constant(17 : index) : i64
    %49 = llvm.mlir.constant(1 : index) : i64
    llvm.br ^bb3(%47 : i64)
  ^bb3(%50: i64):  // 2 preds: ^bb2, ^bb7
    %51 = llvm.icmp "slt" %50, %48 : i64
    llvm.cond_br %51, ^bb4, ^bb8
  ^bb4:  // pred: ^bb3
    %52 = llvm.mlir.constant(0 : index) : i64
    %53 = llvm.mlir.constant(16 : index) : i64
    %54 = llvm.mlir.constant(1 : index) : i64
    llvm.br ^bb5(%52 : i64)
  ^bb5(%55: i64):  // 2 preds: ^bb4, ^bb6
    %56 = llvm.icmp "slt" %55, %53 : i64
    llvm.cond_br %56, ^bb6, ^bb7
  ^bb6:  // pred: ^bb5
    %57 = llvm.mlir.constant(-4.000000e+00 : f64) : f64
    %58 = llvm.extractvalue %19[1] : !llvm.struct<(ptr<f64>, ptr<f64>, i64, array<3 x i64>, array<3 x i64>)>
    %59 = llvm.mlir.constant(288 : index) : i64
    %60 = llvm.mul %45, %59  : i64
    %61 = llvm.mlir.constant(16 : index) : i64
    %62 = llvm.mul %50, %61  : i64
    %63 = llvm.add %60, %62  : i64
    %64 = llvm.add %63, %55  : i64
    %65 = llvm.getelementptr %58[%64] : (!llvm.ptr<f64>, i64) -> !llvm.ptr<f64>
    llvm.store %57, %65 : !llvm.ptr<f64>
    %66 = llvm.add %55, %54  : i64
    llvm.br ^bb5(%66 : i64)
  ^bb7:  // pred: ^bb5
    %67 = llvm.add %50, %49  : i64
    llvm.br ^bb3(%67 : i64)
  ^bb8:  // pred: ^bb3
    %68 = llvm.add %45, %44  : i64
    llvm.br ^bb1(%68 : i64)
  ^bb9:  // pred: ^bb1
    llvm.return
  }
}

then I ran these commands:

mlir-translate --mlir-to-llvmir laplace.mlir > laplace.bc
llc laplace.bc -o laplace.s
clang -c laplace.s -o laplace.o

and build a main.c file:

#include <stdio.h>
void laplace(double input[72][18][16], double output[72][18][16]);
int main(){
    double input[72][18][16];
    double output[72][18][16];
    for(int i=0;i<72;i++){
        for(int j=0;j<18;j++){
            for(int k=0;k<16;k++){
                input[i][j][k] = 1;
            }
        }
    }
    laplace(input, output);
    return 0;
}

linked them:

gcc -c main.c -o main.o
gcc laplace.o main.o -o laplace
./laplace

and got this fault:

Segmentation fault (core dumped)

Any help to run this correctly is appreciated.

2

As you can see, in the LLVM file the function you’re calling is: llvm.func @laplace(%arg0: !llvm.ptr<f64>, %arg1: !llvm.ptr<f64>, %arg2: i64, %arg3: i64, %arg4: i64, %arg5: i64, %arg6: i64, %arg7: i64, %arg8: i64, %arg9: !llvm.ptr<f64>, %arg10: !llvm.ptr<f64>, %arg11: i64, %arg12: i64, %arg13: i64, %arg14: i64, %arg15: i64, %arg16: i64, %arg17: i64) {

But on the C file, from your main you’re only passing it two pointers: this clearly can’t work.
Some information on the calling convention can be found here: LLVM IR Target - MLIR

3

I change the LLVM file to this form, but still get the segmentation fault which may happen at the “llvm.store” instru, I wonder why that is?

module  {
  llvm.func @malloc(i64) -> !llvm.ptr<i8>
  llvm.func @laplace(%arg0: !llvm.ptr<f64>, %arg1: !llvm.ptr<f64>, %arg2: i64, %arg3: i64, %arg4: i64, %arg5: i64, %arg6: i64, %arg7: i64, %arg8: i64, %arg9: !llvm.ptr<f64>, %arg10: !llvm.ptr<f64>, %arg11: i64, %arg12: i64, %arg13: i64, %arg14: i64, %arg15: i64, %arg16: i64, %arg17: i64) {
    %0 = llvm.mlir.undef : !llvm.struct<(ptr<f64>, ptr<f64>, i64, array<3 x i64>, array<3 x i64>)>
    %1 = llvm.insertvalue %arg0, %0[0] : !llvm.struct<(ptr<f64>, ptr<f64>, i64, array<3 x i64>, array<3 x i64>)>
    %2 = llvm.insertvalue %arg1, %1[1] : !llvm.struct<(ptr<f64>, ptr<f64>, i64, array<3 x i64>, array<3 x i64>)>
    %3 = llvm.insertvalue %arg2, %2[2] : !llvm.struct<(ptr<f64>, ptr<f64>, i64, array<3 x i64>, array<3 x i64>)>
    %4 = llvm.insertvalue %arg3, %3[3, 0] : !llvm.struct<(ptr<f64>, ptr<f64>, i64, array<3 x i64>, array<3 x i64>)>
    %5 = llvm.insertvalue %arg6, %4[4, 0] : !llvm.struct<(ptr<f64>, ptr<f64>, i64, array<3 x i64>, array<3 x i64>)>
    %6 = llvm.insertvalue %arg4, %5[3, 1] : !llvm.struct<(ptr<f64>, ptr<f64>, i64, array<3 x i64>, array<3 x i64>)>
    %7 = llvm.insertvalue %arg7, %6[4, 1] : !llvm.struct<(ptr<f64>, ptr<f64>, i64, array<3 x i64>, array<3 x i64>)>
    %8 = llvm.insertvalue %arg5, %7[3, 2] : !llvm.struct<(ptr<f64>, ptr<f64>, i64, array<3 x i64>, array<3 x i64>)>
    %9 = llvm.insertvalue %arg8, %8[4, 2] : !llvm.struct<(ptr<f64>, ptr<f64>, i64, array<3 x i64>, array<3 x i64>)>
    %10 = llvm.mlir.undef : !llvm.struct<(ptr<f64>, ptr<f64>, i64, array<3 x i64>, array<3 x i64>)>
    %11 = llvm.insertvalue %arg9, %10[0] : !llvm.struct<(ptr<f64>, ptr<f64>, i64, array<3 x i64>, array<3 x i64>)>
    %12 = llvm.insertvalue %arg10, %11[1] : !llvm.struct<(ptr<f64>, ptr<f64>, i64, array<3 x i64>, array<3 x i64>)>
    %13 = llvm.insertvalue %arg11, %12[2] : !llvm.struct<(ptr<f64>, ptr<f64>, i64, array<3 x i64>, array<3 x i64>)>
    %14 = llvm.insertvalue %arg12, %13[3, 0] : !llvm.struct<(ptr<f64>, ptr<f64>, i64, array<3 x i64>, array<3 x i64>)>
    %15 = llvm.insertvalue %arg15, %14[4, 0] : !llvm.struct<(ptr<f64>, ptr<f64>, i64, array<3 x i64>, array<3 x i64>)>
    %16 = llvm.insertvalue %arg13, %15[3, 1] : !llvm.struct<(ptr<f64>, ptr<f64>, i64, array<3 x i64>, array<3 x i64>)>
    %17 = llvm.insertvalue %arg16, %16[4, 1] : !llvm.struct<(ptr<f64>, ptr<f64>, i64, array<3 x i64>, array<3 x i64>)>
    %18 = llvm.insertvalue %arg14, %17[3, 2] : !llvm.struct<(ptr<f64>, ptr<f64>, i64, array<3 x i64>, array<3 x i64>)>
    %19 = llvm.insertvalue %arg17, %18[4, 2] : !llvm.struct<(ptr<f64>, ptr<f64>, i64, array<3 x i64>, array<3 x i64>)>
    %20 = llvm.mlir.constant(72 : index) : i64
    %21 = llvm.mlir.constant(18 : index) : i64
    %22 = llvm.mlir.constant(16 : index) : i64
    %23 = llvm.mlir.constant(1 : index) : i64
    %24 = llvm.mlir.constant(288 : index) : i64
    %25 = llvm.mlir.constant(20736 : index) : i64
    %26 = llvm.mlir.null : !llvm.ptr<f64>
    %27 = llvm.getelementptr %26[%25] : (!llvm.ptr<f64>, i64) -> !llvm.ptr<f64>
    %28 = llvm.ptrtoint %27 : !llvm.ptr<f64> to i64
    %29 = llvm.call @malloc(%28) : (i64) -> !llvm.ptr<i8>
    %30 = llvm.bitcast %29 : !llvm.ptr<i8> to !llvm.ptr<f64>
    %31 = llvm.mlir.undef : !llvm.struct<(ptr<f64>, ptr<f64>, i64, array<3 x i64>, array<3 x i64>)>
    %32 = llvm.insertvalue %30, %31[0] : !llvm.struct<(ptr<f64>, ptr<f64>, i64, array<3 x i64>, array<3 x i64>)>
    %33 = llvm.insertvalue %30, %32[1] : !llvm.struct<(ptr<f64>, ptr<f64>, i64, array<3 x i64>, array<3 x i64>)>
    %34 = llvm.mlir.constant(0 : index) : i64
    %35 = llvm.insertvalue %34, %33[2] : !llvm.struct<(ptr<f64>, ptr<f64>, i64, array<3 x i64>, array<3 x i64>)>
    %36 = llvm.insertvalue %20, %35[3, 0] : !llvm.struct<(ptr<f64>, ptr<f64>, i64, array<3 x i64>, array<3 x i64>)>
    %37 = llvm.insertvalue %21, %36[3, 1] : !llvm.struct<(ptr<f64>, ptr<f64>, i64, array<3 x i64>, array<3 x i64>)>
    %38 = llvm.insertvalue %22, %37[3, 2] : !llvm.struct<(ptr<f64>, ptr<f64>, i64, array<3 x i64>, array<3 x i64>)>
    %39 = llvm.insertvalue %24, %38[4, 0] : !llvm.struct<(ptr<f64>, ptr<f64>, i64, array<3 x i64>, array<3 x i64>)>
    %40 = llvm.insertvalue %22, %39[4, 1] : !llvm.struct<(ptr<f64>, ptr<f64>, i64, array<3 x i64>, array<3 x i64>)>
    %41 = llvm.insertvalue %23, %40[4, 2] : !llvm.struct<(ptr<f64>, ptr<f64>, i64, array<3 x i64>, array<3 x i64>)>
    %42 = llvm.mlir.constant(1 : index) : i64
    %43 = llvm.mlir.constant(71 : index) : i64
    %44 = llvm.mlir.constant(1 : index) : i64
    llvm.br ^bb1(%42 : i64)
  ^bb1(%45: i64):  // 2 preds: ^bb0, ^bb8
    %46 = llvm.icmp "slt" %45, %43 : i64
    llvm.cond_br %46, ^bb2, ^bb9
  ^bb2:  // pred: ^bb1
    %47 = llvm.mlir.constant(1 : index) : i64
    %48 = llvm.mlir.constant(17 : index) : i64
    %49 = llvm.mlir.constant(1 : index) : i64
    llvm.br ^bb3(%47 : i64)
  ^bb3(%50: i64):  // 2 preds: ^bb2, ^bb7
    %51 = llvm.icmp "slt" %50, %48 : i64
    llvm.cond_br %51, ^bb4, ^bb8
  ^bb4:  // pred: ^bb3
    %52 = llvm.mlir.constant(0 : index) : i64
    %53 = llvm.mlir.constant(16 : index) : i64
    %54 = llvm.mlir.constant(1 : index) : i64
    llvm.br ^bb5(%52 : i64)
  ^bb5(%55: i64):  // 2 preds: ^bb4, ^bb6
    %56 = llvm.icmp "slt" %55, %53 : i64
    llvm.cond_br %56, ^bb6, ^bb7
  ^bb6:  // pred: ^bb5
    %57 = llvm.mlir.constant(-4.000000e+00 : f64) : f64
    %58 = llvm.extractvalue %19[1] : !llvm.struct<(ptr<f64>, ptr<f64>, i64, array<3 x i64>, array<3 x i64>)>
    %59 = llvm.mlir.constant(288 : index) : i64
    %60 = llvm.mul %45, %59  : i64
    %61 = llvm.mlir.constant(16 : index) : i64
    %62 = llvm.mul %50, %61  : i64
    %63 = llvm.add %60, %62  : i64
    %64 = llvm.add %63, %55  : i64
    %65 = llvm.getelementptr %58[%64] : (!llvm.ptr<f64>, i64) -> !llvm.ptr<f64>
    llvm.store %57, %65 : !llvm.ptr<f64>
    %66 = llvm.add %55, %54  : i64
    llvm.br ^bb5(%66 : i64)
  ^bb7:  // pred: ^bb5
    %67 = llvm.add %50, %49  : i64
    llvm.br ^bb3(%67 : i64)
  ^bb8:  // pred: ^bb3
    %68 = llvm.add %45, %44  : i64
    llvm.br ^bb1(%68 : i64)
  ^bb9:  // pred: ^bb1
    llvm.return
  }

  llvm.func @_mlir_ciface_laplace(%arg0: !llvm.ptr<struct<(ptr<f64>, ptr<f64>, i64, array<3 x i64>, array<3 x i64>)>>, %arg1: !llvm.ptr<struct<(ptr<f64>, ptr<f64>, i64, array<3 x i64>, array<3 x i64>)>>) {
    %0 = llvm.load %arg0 : !llvm.ptr<struct<(ptr<f64>, ptr<f64>, i64, array<3 x i64>, array<3 x i64>)>>
    %1 = llvm.extractvalue %0[0] : !llvm.struct<(ptr<f64>, ptr<f64>, i64, array<3 x i64>, array<3 x i64>)>
    %2 = llvm.extractvalue %0[1] : !llvm.struct<(ptr<f64>, ptr<f64>, i64, array<3 x i64>, array<3 x i64>)>
    %3 = llvm.extractvalue %0[2] : !llvm.struct<(ptr<f64>, ptr<f64>, i64, array<3 x i64>, array<3 x i64>)>
    %4 = llvm.extractvalue %0[3, 0] : !llvm.struct<(ptr<f64>, ptr<f64>, i64, array<3 x i64>, array<3 x i64>)>
    %5 = llvm.extractvalue %0[3, 1] : !llvm.struct<(ptr<f64>, ptr<f64>, i64, array<3 x i64>, array<3 x i64>)>
    %6 = llvm.extractvalue %0[3, 2] : !llvm.struct<(ptr<f64>, ptr<f64>, i64, array<3 x i64>, array<3 x i64>)>
    %7 = llvm.extractvalue %0[4, 0] : !llvm.struct<(ptr<f64>, ptr<f64>, i64, array<3 x i64>, array<3 x i64>)>
    %8 = llvm.extractvalue %0[4, 1] : !llvm.struct<(ptr<f64>, ptr<f64>, i64, array<3 x i64>, array<3 x i64>)>
    %9 = llvm.extractvalue %0[4, 2] : !llvm.struct<(ptr<f64>, ptr<f64>, i64, array<3 x i64>, array<3 x i64>)>
    %10 = llvm.load %arg1 : !llvm.ptr<struct<(ptr<f64>, ptr<f64>, i64, array<3 x i64>, array<3 x i64>)>>
    %11 = llvm.extractvalue %10[0] : !llvm.struct<(ptr<f64>, ptr<f64>, i64, array<3 x i64>, array<3 x i64>)>
    %12 = llvm.extractvalue %10[1] : !llvm.struct<(ptr<f64>, ptr<f64>, i64, array<3 x i64>, array<3 x i64>)>
    %13 = llvm.extractvalue %10[2] : !llvm.struct<(ptr<f64>, ptr<f64>, i64, array<3 x i64>, array<3 x i64>)>
    %14 = llvm.extractvalue %10[3, 0] : !llvm.struct<(ptr<f64>, ptr<f64>, i64, array<3 x i64>, array<3 x i64>)>
    %15 = llvm.extractvalue %10[3, 1] : !llvm.struct<(ptr<f64>, ptr<f64>, i64, array<3 x i64>, array<3 x i64>)>
    %16 = llvm.extractvalue %10[3, 2] : !llvm.struct<(ptr<f64>, ptr<f64>, i64, array<3 x i64>, array<3 x i64>)>
    %17 = llvm.extractvalue %10[4, 0] : !llvm.struct<(ptr<f64>, ptr<f64>, i64, array<3 x i64>, array<3 x i64>)>
    %18 = llvm.extractvalue %10[4, 1] : !llvm.struct<(ptr<f64>, ptr<f64>, i64, array<3 x i64>, array<3 x i64>)>
    %19 = llvm.extractvalue %10[4, 2] : !llvm.struct<(ptr<f64>, ptr<f64>, i64, array<3 x i64>, array<3 x i64>)>
    llvm.call @laplace(%1, %2, %3, %4, %5, %6, %7, %8, %9, %11, %12, %13, %14, %15, %16, %17, %18, %19) : (!llvm.ptr<f64>, !llvm.ptr<f64>, i64, i64, i64, i64, i64, i64, i64, !llvm.ptr<f64>, !llvm.ptr<f64>, i64, i64, i64, i64, i64, i64, i64) -> ()
    llvm.return
  }
}
4

Now we don’t know how this function is called. You need to make sure that correct sizes and strides are passed for each memref, there is no mechanism to “infer” them from C.

5

the c file I used to call this function is as follow:

#include <stdio.h>
void _mlir_ciface_laplace(double input[72][18][16], double output[72][18][16]);
int main(){
    double input[72][18][16];
    double output[72][18][16];
    for(int i=0;i<72;i++){
        for(int j=0;j<18;j++){
            for(int k=0;k<16;k++){
                input[i][j][k] = 1;
            }
        }
    }
    _mlir_ciface_laplace(input, output);
    return 0;
}

and the original mlir file before lowering is as follow:

module  {
  func @laplace(%arg0: memref<72x18x16xf64>, %arg1: memref<72x18x16xf64>) {
    %0 = memref.alloc() : memref<72x18x16xf64>
    affine.for %arg2 = 1 to 71 {
      affine.for %arg3 = 1 to 17 {
        affine.for %arg4 = 0 to 16 {
          %cst = constant -4.000000e+00 : f64
          affine.store %cst, %arg1[%arg2, %arg3, %arg4] : memref<72x18x16xf64>
        }
      }
    }
    return
  }
}

Is there anything wrong?

6

The way the function is called is wrong. The signature for _mlir_ciface_laplace in LLVM dialect is @_mlir_ciface_laplace(%arg0: !llvm.ptr<struct<(ptr<f64>, ptr<f64>, i64, array<3 x i64>, array<3 x i64>)>>, %arg1: !llvm.ptr<struct<(ptr<f64>, ptr<f64>, i64, array<3 x i64>, array<3 x i64>)>>) (in LLVM IR, it would be void @_mlir_ciface_laplace({f64*, f64*, i64, [3 x i64], [3 x i64]}*, {f64*, f64*, i64, [3 x i64], [3 x i64]}*)) and you are passing f64*, f64* to it. This will not work. Memrefs are NOT pointers. Please make sure to read and understand the calling convention document Mehdi linked above.

7

I opened âš™ D117072 Add an example of integration test invoking MLIR source with Memref from C so that we have an example of this in-tree.

1 Like
8

Thanks for your example!