[llvm-dev] ORC JIT error when using AVX2 vector instructions

Frank Winter via llvm-dev llvm-dev at lists.llvm.org
Mon Aug 30 12:08:35 PDT 2021


Hi.

As soon as the module contains instructions operating on < 8 x float > the ORC JIT refuses to work.

Here's the module that provokes the error given further below:

; ModuleID = 'module'
source_filename = "module"
target datalayout = "e-m:e-p270:32:32-p271:32:32-p272:64:64-i64:64-f80:128-n8:16:32:64-S128"

define private void @eval0_intern(i32 %arg0, i32 %arg1, <8 x float>* %arg2, <8 x float>* %arg3, <8 x float>* %arg4) {
stack:
  br label %afterstack

afterstack:                                       ; preds = %stack
  %0 = add nsw i32 %arg0, %arg1
  %1 = add nsw i32 0, %0
  %2 = mul i32 %1, 1
  %3 = add nsw i32 %2, 0
  %4 = mul i32 %3, 1
  %5 = add nsw i32 %4, 0
  %6 = mul i32 %5, 1
  %7 = add nsw i32 %6, 0
  %8 = mul i32 %7, 8
  %9 = getelementptr <8 x float>, <8 x float>* %arg3, i32 %8
  %10 = load <8 x float>, <8 x float>* %9, align 32
  %11 = add nsw i32 0, %0
  %12 = mul i32 %11, 1
  %13 = add nsw i32 %12, 0
  %14 = mul i32 %13, 1
  %15 = add nsw i32 %14, 0
  %16 = mul i32 %15, 1
  %17 = add nsw i32 %16, 0
  %18 = mul i32 %17, 8
  %19 = getelementptr <8 x float>, <8 x float>* %arg4, i32 %18
  %20 = load <8 x float>, <8 x float>* %19, align 32
  %21 = mul <8 x float> %20, %10
  %22 = add nsw i32 0, %0
  %23 = mul i32 %22, 1
  %24 = add nsw i32 %23, 0
  %25 = mul i32 %24, 1
  %26 = add nsw i32 %25, 0
  %27 = mul i32 %26, 1
  %28 = add nsw i32 %27, 0
  %29 = mul i32 %28, 8
  %30 = getelementptr <8 x float>, <8 x float>* %arg2, i32 %29
  store <8 x float> %21, <8 x float>* %30, align 32
  ret void
}

define void @eval0(i32 %idx, [8 x i8]* %arg_ptr) {
entrypoint:
  %0 = getelementptr [8 x i8], [8 x i8]* %arg_ptr, i32 0
  %1 = bitcast [8 x i8]* %0 to i32*
  %2 = load i32, i32* %1, align 4
  %3 = getelementptr [8 x i8], [8 x i8]* %arg_ptr, i32 1
  %4 = bitcast [8 x i8]* %3 to <8 x float>**
  %5 = load <8 x float>*, <8 x float>** %4, align 8
  %6 = getelementptr [8 x i8], [8 x i8]* %arg_ptr, i32 2
  %7 = bitcast [8 x i8]* %6 to <8 x float>**
  %8 = load <8 x float>*, <8 x float>** %7, align 8
  %9 = getelementptr [8 x i8], [8 x i8]* %arg_ptr, i32 3
  %10 = bitcast [8 x i8]* %9 to <8 x float>**
  %11 = load <8 x float>*, <8 x float>** %10, align 8
  call void @eval0_intern(i32 %idx, i32 %2, <8 x float>* %5, <8 x float>* %8, <8 x float>* %11)
  ret void
}
--------------------------


For the JIT part I'm using the Kaleidoscope ORC JIT as given in the LLVM examples. However, when it comes to the symbol lookup the program stops with output like this:

Lookup
LLVM ERROR: Cannot select: 0x562e8bb6c268: v4f32 = mul 0x562e8bb6bab0, 0x562e8bb6b6a0
  0x562e8bb6bab0: v4f32,ch = load<(load 16 from %ir.19 + 16, basealign 32)> 0x562e8baf8ca8, 0x562e8bb6c130, undef:i64
    0x562e8bb6c130: i64 = add nuw 0x562e8bb6bcb8, Constant:i64<16>
      0x562e8bb6bcb8: i64 = add 0x562e8bb6bc50, 0x562e8bb6b9e0
        0x562e8bb6bc50: i64,ch = CopyFromReg 0x562e8baf8ca8, Register:i64 %4
          0x562e8bb6bbe8: i64 = Register %4
        0x562e8bb6b9e0: i64 = shl 0x562e8bb6b910, Constant:i8<5>
          0x562e8bb6b910: i64 = sign_extend 0x562e8bb6b770
            0x562e8bb6b770: i32 = shl 0x562e8bb6b500, Constant:i8<3>
              0x562e8bb6b500: i32 = add nsw 0x562e8bb6b3c8, 0x562e8bb6b498
                0x562e8bb6b3c8: i32,ch = CopyFromReg 0x562e8baf8ca8, Register:i32 %0
                  0x562e8bb6b360: i32 = Register %0
                0x562e8bb6b498: i32,ch = CopyFromReg 0x562e8baf8ca8, Register:i32 %1
                  0x562e8bb6b430: i32 = Register %1
              0x562e8bb6ea28: i8 = Constant<3>
          0x562e8bb6c2d0: i8 = Constant<5>
      0x562e8bb6b638: i64 = Constant<16>
    0x562e8bb6bb18: i64 = undef
  0x562e8bb6b6a0: v4f32,ch = load<(load 16 from %ir.9 + 16, basealign 32)> 0x562e8baf8ca8, 0x562e8bb6c198, undef:i64
    0x562e8bb6c198: i64 = add nuw 0x562e8bb6ba48, Constant:i64<16>
      0x562e8bb6ba48: i64 = add 0x562e8bb6b8a8, 0x562e8bb6b9e0
        0x562e8bb6b8a8: i64,ch = CopyFromReg 0x562e8baf8ca8, Register:i64 %3
          0x562e8bb6b840: i64 = Register %3
        0x562e8bb6b9e0: i64 = shl 0x562e8bb6b910, Constant:i8<5>
          0x562e8bb6b910: i64 = sign_extend 0x562e8bb6b770
            0x562e8bb6b770: i32 = shl 0x562e8bb6b500, Constant:i8<3>
              0x562e8bb6b500: i32 = add nsw 0x562e8bb6b3c8, 0x562e8bb6b498
                0x562e8bb6b3c8: i32,ch = CopyFromReg 0x562e8baf8ca8, Register:i32 %0
                  0x562e8bb6b360: i32 = Register %0
                0x562e8bb6b498: i32,ch = CopyFromReg 0x562e8baf8ca8, Register:i32 %1
                  0x562e8bb6b430: i32 = Register %1
              0x562e8bb6ea28: i8 = Constant<3>
          0x562e8bb6c2d0: i8 = Constant<5>
      0x562e8bb6b638: i64 = Constant<16>
    0x562e8bb6bb18: i64 = undef


The module compiles fine with LLC. So, I assume that's not the problem.

What might go wrong? Is there a way to initialize the ORC JIT with the AVX2 option somehow?

This is using LLVM release 12.

Best,
Frank

-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://lists.llvm.org/pipermail/llvm-dev/attachments/20210830/82e1c948/attachment.html>


More information about the llvm-dev mailing list