[clang] caff859 - [OpenMP] Simplify pointer comparison

[Nikita Popov via cfe-commits]

Author: Nikita Popov
Date: 2022-01-25T12:38:37+01:00
New Revision: caff8591eff211c41d8de8505f89754d09ca6fa7

URL: https://github.com/llvm/llvm-project/commit/caff8591eff211c41d8de8505f89754d09ca6fa7
DIFF: https://github.com/llvm/llvm-project/commit/caff8591eff211c41d8de8505f89754d09ca6fa7.diff

LOG: [OpenMP] Simplify pointer comparison

Rather than checking ptrdiff(a, b) != 0, directly check a != b.

Added: 
    

Modified: 
    clang/lib/CodeGen/CGOpenMPRuntime.cpp
    clang/test/OpenMP/declare_mapper_codegen.cpp

Removed: 
    


################################################################################
diff  --git a/clang/lib/CodeGen/CGOpenMPRuntime.cpp b/clang/lib/CodeGen/CGOpenMPRuntime.cpp
index c8c08060e729e..233656b90095b 100644
--- a/clang/lib/CodeGen/CGOpenMPRuntime.cpp
+++ b/clang/lib/CodeGen/CGOpenMPRuntime.cpp
@@ -10217,8 +10217,7 @@ void CGOpenMPRuntime::emitUDMapperArrayInitOrDel(
   llvm::Value *Cond;
   if (IsInit) {
     // base != begin?
-    llvm::Value *BaseIsBegin = MapperCGF.Builder.CreateIsNotNull(
-        MapperCGF.Builder.CreatePtrDiff(Base, Begin));
+    llvm::Value *BaseIsBegin = MapperCGF.Builder.CreateICmpNE(Base, Begin);
     // IsPtrAndObj?
     llvm::Value *PtrAndObjBit = MapperCGF.Builder.CreateAnd(
         MapType,

diff  --git a/clang/test/OpenMP/declare_mapper_codegen.cpp b/clang/test/OpenMP/declare_mapper_codegen.cpp
index 053aa9d2cc6df..e114a1315c79f 100644
--- a/clang/test/OpenMP/declare_mapper_codegen.cpp
+++ b/clang/test/OpenMP/declare_mapper_codegen.cpp
@@ -102,11 +102,7 @@ class C {
 // CK0-DAG: [[ISARRAY:%.+]] = icmp sgt i64 [[SIZE]], 1
 // CK0-DAG: [[PTRBEGIN:%.+]] = bitcast i8* [[BEGIN]] to %class.C*
 // CK0-DAG: [[PTREND:%.+]] = getelementptr %class.C, %class.C* [[PTRBEGIN]], i64 [[SIZE]]
-// CK0-DAG: [[BPTRI:%.+]] = ptrtoint i8* [[BPTR]] to i64
-// CK0-DAG: [[PTRI:%.+]] = ptrtoint i8* [[BEGIN]] to i64
-// CK0-DAG: [[DIF:%.+]] = sub i64 [[BPTRI]], [[PTRI]]
-// CK0-DAG: [[NORM:%.+]] = sdiv exact i64 [[DIF]], ptrtoint (i8* getelementptr (i8, i8* null, i32 1) to i64)
-// CK0-DAG: [[PTRSNE:%.+]] = icmp ne i64 [[NORM]], 0
+// CK0-DAG: [[PTRSNE:%.+]] = icmp ne i8* [[BPTR]], [[BEGIN]]
 // CK0-DAG: [[PTRANDOBJ:%.+]] = and i64 [[TYPE]], 16
 // CK0-DAG: [[ISPTRANDOBJ:%.+]] = icmp ne i64 [[PTRANDOBJ]], 0
 // CK0-DAG: [[CMPA:%.+]] = and i1 [[PTRSNE]], [[ISPTRANDOBJ]]
@@ -662,11 +658,7 @@ class C {
 // CK1-DAG: [[PTRBEGIN:%.+]] = bitcast i8* [[BEGIN]] to %class.C*
 // CK1-DAG: [[PTREND:%.+]] = getelementptr %class.C, %class.C* [[PTRBEGIN]], i64 [[SIZE]]
 // CK1-DAG: [[ISARRAY:%.+]] = icmp sgt i64 [[SIZE]], 1
-// CK1-DAG: [[BPTRI:%.+]] = ptrtoint i8* [[BPTR]] to i64
-// CK1-DAG: [[PTRI:%.+]] = ptrtoint i8* [[BEGIN]] to i64
-// CK1-DAG: [[DIF:%.+]] = sub i64 [[BPTRI]], [[PTRI]]
-// CK1-DAG: [[NORM:%.+]] = sdiv exact i64 [[DIF]], ptrtoint (i8* getelementptr (i8, i8* null, i32 1) to i64)
-// CK1-DAG: [[PTRSNE:%.+]] = icmp ne i64 [[NORM]], 0
+// CK1-DAG: [[PTRSNE:%.+]] = icmp ne i8* [[BPTR]], [[BEGIN]]
 // CK1-DAG: [[PTRANDOBJ:%.+]] = and i64 [[TYPE]], 16
 // CK1-DAG: [[ISPTRANDOBJ:%.+]] = icmp ne i64 [[PTRANDOBJ]], 0
 // CK1-DAG: [[CMPA:%.+]] = and i1 [[PTRSNE]], [[ISPTRANDOBJ]]
@@ -789,11 +781,7 @@ class C {
 // CK2-DAG: [[PTRBEGIN:%.+]] = bitcast i8* [[BEGIN]] to %class.C*
 // CK2-DAG: [[PTREND:%.+]] = getelementptr %class.C, %class.C* [[PTRBEGIN]], i64 [[SIZE]]
 // CK2-DAG: [[ISARRAY:%.+]] = icmp sgt i64 [[SIZE]], 1
-// CK2-DAG: [[BPTRI:%.+]] = ptrtoint i8* [[BPTR]] to i64
-// CK2-DAG: [[PTRI:%.+]] = ptrtoint i8* [[BEGIN]] to i64
-// CK2-DAG: [[DIF:%.+]] = sub i64 [[BPTRI]], [[PTRI]]
-// CK2-DAG: [[NORM:%.+]] = sdiv exact i64 [[DIF]], ptrtoint (i8* getelementptr (i8, i8* null, i32 1) to i64)
-// CK2-DAG: [[PTRSNE:%.+]] = icmp ne i64 [[NORM]], 0
+// CK2-DAG: [[PTRSNE:%.+]] = icmp ne i8* [[BPTR]], [[BEGIN]]
 // CK2-DAG: [[PTRANDOBJ:%.+]] = and i64 [[TYPE]], 16
 // CK2-DAG: [[ISPTRANDOBJ:%.+]] = icmp ne i64 [[PTRANDOBJ]], 0
 // CK2-DAG: [[CMPA:%.+]] = and i1 [[PTRSNE]], [[ISPTRANDOBJ]]
@@ -999,11 +987,7 @@ class C {
 // CK4-DAG: [[PTRBEGIN:%.+]] = bitcast i8* [[BEGIN]] to %class.C*
 // CK4-DAG: [[PTREND:%.+]] = getelementptr %class.C, %class.C* [[PTRBEGIN]], i64 [[SIZE]]
 // CK4-DAG: [[ISARRAY:%.+]] = icmp sgt i64 [[SIZE]], 1
-// CK4-DAG: [[BPTRI:%.+]] = ptrtoint i8* [[BPTR]] to i64
-// CK4-DAG: [[PTRI:%.+]] = ptrtoint i8* [[BEGIN]] to i64
-// CK4-DAG: [[DIF:%.+]] = sub i64 [[BPTRI]], [[PTRI]]
-// CK4-DAG: [[NORM:%.+]] = sdiv exact i64 [[DIF]], ptrtoint (i8* getelementptr (i8, i8* null, i32 1) to i64)
-// CK4-DAG: [[PTRSNE:%.+]] = icmp ne i64 [[NORM]], 0
+// CK4-DAG: [[PTRSNE:%.+]] = icmp ne i8* [[BPTR]], [[BEGIN]]
 // CK4-DAG: [[PTRANDOBJ:%.+]] = and i64 [[TYPE]], 16
 // CK4-DAG: [[ISPTRANDOBJ:%.+]] = icmp ne i64 [[PTRANDOBJ]], 0
 // CK4-DAG: [[CMPA:%.+]] = and i1 [[PTRSNE]], [[ISPTRANDOBJ]]