[llvm] 334c1ab - Add regression tests from ConstantData uselist removal (#138960)

[via llvm-commits]

Author: Matt Arsenault
Date: 2025-05-08T07:57:13+02:00
New Revision: 334c1abdb0bee488477f810ebf4cc1d41c31e653

URL: https://github.com/llvm/llvm-project/commit/334c1abdb0bee488477f810ebf4cc1d41c31e653
DIFF: https://github.com/llvm/llvm-project/commit/334c1abdb0bee488477f810ebf4cc1d41c31e653.diff

LOG: Add regression tests from ConstantData uselist removal (#138960)

Add some examples of failures after 87f312aad6ede636cd2de5d18f3058bf2caf5651

Added: 
    llvm/test/CodeGen/X86/codegen-no-uselist-constantdata.ll
    llvm/test/Transforms/CorrelatedValuePropagation/no-uselist-constantdata-regression.ll

Modified: 
    

Removed: 
    


################################################################################
diff  --git a/llvm/test/CodeGen/X86/codegen-no-uselist-constantdata.ll b/llvm/test/CodeGen/X86/codegen-no-uselist-constantdata.ll
new file mode 100644
index 0000000000000..fef2c18b30a82
--- /dev/null
+++ b/llvm/test/CodeGen/X86/codegen-no-uselist-constantdata.ll
@@ -0,0 +1,52 @@
+; NOTE: Assertions have been autogenerated by utils/update_llc_test_checks.py UTC_ARGS: --version 5
+; RUN: llc -mtriple=x86_64-unknown-linux-gnu < %s | FileCheck %s
+
+; Make sure codegen doesn't try to inspect the use list of constants
+
+; Make sure we do not try to make use of the uselist of a constant
+; null when looking for the alignment of the pointer.
+define <2 x i32> @no_uselist_null_isDereferenceableAndAlignedPointer(i1 %arg0, ptr align(4) %arg) {
+; CHECK-LABEL: no_uselist_null_isDereferenceableAndAlignedPointer:
+; CHECK:       # %bb.0:
+; CHECK-NEXT:    xorl %eax, %eax
+; CHECK-NEXT:    testb $1, %dil
+; CHECK-NEXT:    cmoveq %rsi, %rax
+; CHECK-NEXT:    movss {{.*#+}} xmm0 = mem[0],zero,zero,zero
+; CHECK-NEXT:    retq
+  %select.ptr = select i1 %arg0, ptr null, ptr %arg
+  %load = load i32, ptr %select.ptr
+  %insert = insertelement <2 x i32> zeroinitializer, i32 %load, i64 0
+  ret <2 x i32> %insert
+}
+
+; Make sure we do not try to inspect the uselist of a constant null
+; when processing a memcpy
+define void @gep_nullptr_no_inspect_uselist(ptr %arg) {
+; CHECK-LABEL: gep_nullptr_no_inspect_uselist:
+; CHECK:       # %bb.0:
+; CHECK-NEXT:    movzbl 16, %eax
+; CHECK-NEXT:    movb %al, (%rdi)
+; CHECK-NEXT:    retq
+  %null_gep = getelementptr i8, ptr null, i64 16
+  call void @llvm.memcpy.p0.p0.i64(ptr %arg, ptr %null_gep, i64 1, i1 false)
+  ret void
+}
+
+define <16 x i8> @load_null_offset() {
+; CHECK-LABEL: load_null_offset:
+; CHECK:       # %bb.0:
+; CHECK-NEXT:    movzbl 11, %eax
+; CHECK-NEXT:    movd %eax, %xmm1
+; CHECK-NEXT:    pslld $8, %xmm1
+; CHECK-NEXT:    xorps %xmm0, %xmm0
+; CHECK-NEXT:    movss {{.*#+}} xmm0 = xmm1[0],xmm0[1,2,3]
+; CHECK-NEXT:    retq
+  %gep.null = getelementptr i8, ptr null, i64 11
+  %load = load i8, ptr %gep.null, align 1
+  %insert = insertelement <16 x i8> zeroinitializer, i8 %load, i64 1
+  ret <16 x i8> %insert
+}
+
+declare void @llvm.memcpy.p0.p0.i64(ptr noalias writeonly captures(none), ptr noalias readonly captures(none), i64, i1 immarg) #0
+
+attributes #0 = { nocallback nofree nounwind willreturn memory(argmem: readwrite) }

diff  --git a/llvm/test/Transforms/CorrelatedValuePropagation/no-uselist-constantdata-regression.ll b/llvm/test/Transforms/CorrelatedValuePropagation/no-uselist-constantdata-regression.ll
new file mode 100644
index 0000000000000..51be78788c454
--- /dev/null
+++ b/llvm/test/Transforms/CorrelatedValuePropagation/no-uselist-constantdata-regression.ll
@@ -0,0 +1,30 @@
+; NOTE: Assertions have been autogenerated by utils/update_test_checks.py UTC_ARGS: --version 5
+; RUN: opt -S -passes=correlated-propagation < %s | FileCheck %s
+
+; Test for regression after 87f312aad6e from trying to use the uselist of constantdata
+
+define ptr @_ZN4mlir6Region15getParentOfTypeINS_19FunctionOpInterfaceEEET_v() {
+; CHECK-LABEL: define ptr @_ZN4mlir6Region15getParentOfTypeINS_19FunctionOpInterfaceEEET_v() {
+; CHECK-NEXT:  [[ENTRY:.*:]]
+; CHECK-NEXT:    [[CALL_FCA_0_EXTRACT:%.*]] = extractvalue [2 x i64] zeroinitializer, 0
+; CHECK-NEXT:    [[I2P:%.*]] = inttoptr i64 [[CALL_FCA_0_EXTRACT]] to ptr
+; CHECK-NEXT:    [[CMP_I:%.*]] = icmp ne ptr [[I2P]], null
+; CHECK-NEXT:    br i1 [[CMP_I]], label %[[CLEANUP:.*]], label %[[DO_COND:.*]]
+; CHECK:       [[DO_COND]]:
+; CHECK-NEXT:    br label %[[CLEANUP]]
+; CHECK:       [[CLEANUP]]:
+; CHECK-NEXT:    ret ptr [[I2P]]
+;
+entry:
+  %call.fca.0.extract = extractvalue [2 x i64] zeroinitializer, 0
+  %i2p = inttoptr i64 %call.fca.0.extract to ptr
+  %cmp.i = icmp ne ptr %i2p, null
+  br i1 %cmp.i, label %cleanup, label %do.cond
+
+do.cond:                                          ; preds = %entry
+  br label %cleanup
+
+cleanup:                                          ; preds = %do.cond, %entry
+  %phi = phi ptr [ %i2p, %entry ], [ null, %do.cond ]
+  ret ptr %phi
+}