[Hexagon] Explicitly truncate constant in UAddSubO by androm3da · Pull Request #127360 · llvm/llvm-project (original) (raw)

@llvm/pr-subscribers-backend-hexagon

Author: Brian Cain (androm3da)

Changes

After #117558 landed, this code would assert "Value is not an N-bit unsigned value" in getConstant(), from a test case in zig.

Co-authored-by: Craig Topper craig.topper@sifive.com
Fixes #127296

Full diff: https://github.com/llvm/llvm-project/pull/127360.diff

2 Files Affected:

• (modified) llvm/lib/Target/Hexagon/HexagonISelLowering.cpp (+1-1)
• (added) llvm/test/CodeGen/Hexagon/iss127296.ll (+22)

diff --git a/llvm/lib/Target/Hexagon/HexagonISelLowering.cpp b/llvm/lib/Target/Hexagon/HexagonISelLowering.cpp index 1a7667fe42fbc..b31360b4096da 100644 --- a/llvm/lib/Target/Hexagon/HexagonISelLowering.cpp +++ b/llvm/lib/Target/Hexagon/HexagonISelLowering.cpp @@ -3273,7 +3273,7 @@ HexagonTargetLowering::LowerUAddSubO(SDValue Op, SelectionDAG &DAG) const { if (Opc == ISD::USUBO) { SDValue Op = DAG.getNode(ISD::SUB, dl, VTs.VTs[0], {X, Y}); SDValue Ov = DAG.getSetCC(dl, MVT::i1, Op,

•                            DAG.getConstant(-1, dl, ty(Op)), ISD::SETEQ);

•                            DAG.getAllOnesConstant(dl, ty(Op)), ISD::SETEQ);
   return DAG.getMergeValues({Op, Ov}, dl);

  } } diff --git a/llvm/test/CodeGen/Hexagon/iss127296.ll b/llvm/test/CodeGen/Hexagon/iss127296.ll new file mode 100644 index 0000000000000..ad2c5e40a9f02 --- /dev/null +++ b/llvm/test/CodeGen/Hexagon/iss127296.ll @@ -0,0 +1,22 @@ +; RUN: llc -mtriple=hexagon -O0 < %s | FileCheck %s +; REQUIRES: asserts
• +target datalayout = "e-m:e-p:32:32:32-a:0-n16:32-i64:64:64-i32:32:32-i16:16:16-i1:8:8-f32:32:32-f64:64:64-v32:32:32-v64:64:64-v512:512:512-v1024:1024:1024-v2048:2048:2048" +target triple = "hexagon-unknown-linux4.19.0-musl"
• +; CHECK: r0 = #-1
• +define fastcc void @os.linux.tls.initStatic() {
• %1 = call { i32, i1 } @llvm.usub.with.overflow.i32(i32 0, i32 1)
• br label %2
• 2: ; preds = %0
• %3 = extractvalue { i32, i1 } %1, 0
• ret void +}
• +; Function Attrs: nocallback nofree nosync nounwind speculatable willreturn memory(none) +declare { i32, i1 } @llvm.usub.with.overflow.i32(i32, i32) #0
• +attributes #0 = { nocallback nofree nosync nounwind speculatable willreturn memory(none) }