[MLIR][LLVM] Fix #llvm.constant_range parsing

[Kuree]

This should fix #122996.

When APInt parses negative numbers, it may extend the bit width. This patch ensures the bit width matches with the attribute.

[llvmbot]

@llvm/pr-subscribers-mlir-llvm

@llvm/pr-subscribers-mlir

Author: Keyi Zhang (Kuree)

Changes

This should fix #122996.

When APInt parses negative numbers, it may extend the bit width. This patch ensures the bit width matches with the attribute.

---

Full diff: https://github.com/llvm/llvm-project/pull/123009.diff

2 Files Affected:

• (modified) mlir/lib/Dialect/LLVMIR/IR/LLVMAttrs.cpp (+3-4)
• (modified) mlir/test/Dialect/LLVMIR/func.mlir (+6)

diff --git a/mlir/lib/Dialect/LLVMIR/IR/LLVMAttrs.cpp b/mlir/lib/Dialect/LLVMIR/IR/LLVMAttrs.cpp
index ff1636bc121b64..99d6e95c134d8d 100644
--- a/mlir/lib/Dialect/LLVMIR/IR/LLVMAttrs.cpp
+++ b/mlir/lib/Dialect/LLVMIR/IR/LLVMAttrs.cpp
@@ -271,10 +271,9 @@ Attribute ConstantRangeAttr::parse(AsmParser &parser, Type odsType) {
       parser.parseInteger(upper) || parser.parseGreater())
     return Attribute{};
   // For some reason, 0 is always parsed as 64-bits, fix that if needed.
-  if (lower.isZero())
-    lower = lower.sextOrTrunc(bitWidth);
-  if (upper.isZero())
-    upper = upper.sextOrTrunc(bitWidth);
+  // Negative numbers may use more bits than `bitWidth`
+  lower = lower.sextOrTrunc(bitWidth);
+  upper = upper.sextOrTrunc(bitWidth);
   return parser.getChecked<ConstantRangeAttr>(loc, parser.getContext(), lower,
                                               upper);
 }
diff --git a/mlir/test/Dialect/LLVMIR/func.mlir b/mlir/test/Dialect/LLVMIR/func.mlir
index e2a444c1faaba1..74dd862ce8fb26 100644
--- a/mlir/test/Dialect/LLVMIR/func.mlir
+++ b/mlir/test/Dialect/LLVMIR/func.mlir
@@ -479,3 +479,9 @@ llvm.func @intel_reqd_sub_group_size_hint() attributes {llvm.intel_reqd_sub_grou
 // CHECK-SAME: llvm.workgroup_attribution = #llvm.mlir.workgroup_attribution<512 : i64, i32>
 // CHECK-SAME: llvm.workgroup_attribution = #llvm.mlir.workgroup_attribution<128 : i64, !llvm.struct<(i32, i64, f32)>
 llvm.func @workgroup_attribution(%arg0: !llvm.ptr {llvm.workgroup_attribution = #llvm.mlir.workgroup_attribution<512 : i64, i32>}, %arg1: !llvm.ptr {llvm.workgroup_attribution = #llvm.mlir.workgroup_attribution<128 : i64, !llvm.struct<(i32, i64, f32)>>})
+
+// -----
+
+// CHECK: @constant_range_negative
+// CHECK-SAME: llvm.range = #llvm.constant_range<i32, 0, -2147483648>
+llvm.func @constant_range_negative() -> (i32 {llvm.range = #llvm.constant_range<i32, 0, -2147483648>})