When loading from a constant, fold inttoptr if the integer type and the resulting pointer type both have the same size.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@124987 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/lib/Analysis/ConstantFolding.cpp b/lib/Analysis/ConstantFolding.cpp
index 2436110..6c99ad3 100644
--- a/lib/Analysis/ConstantFolding.cpp
+++ b/lib/Analysis/ConstantFolding.cpp
@@ -340,6 +340,17 @@
return true;
}
+ if (ConstantExpr *CE = dyn_cast<ConstantExpr>(C)) {
+ if (CE->getOpcode() == Instruction::IntToPtr) {
+ uint64_t PtrSize = TD.getTypeAllocSize(C->getType());
+ uint64_t IntSize = TD.getTypeAllocSize(C->getOperand(0)->getType());
+
+ if (PtrSize == IntSize)
+ return ReadDataFromGlobal(CE->getOperand(0), ByteOffset, CurPtr,
+ BytesLeft, TD);
+ }
+ }
+
// Otherwise, unknown initializer type.
return false;
}
diff --git a/test/Transforms/ConstProp/loads.ll b/test/Transforms/ConstProp/loads.ll
index 9fbba2b..74d80aa 100644
--- a/test/Transforms/ConstProp/loads.ll
+++ b/test/Transforms/ConstProp/loads.ll
@@ -120,3 +120,20 @@
; CHECK: @test13
; CHECK: ret i1 false
}
+
+@g6 = constant [2 x i8*] [i8* inttoptr (i64 1 to i8*), i8* inttoptr (i64 2 to i8*)]
+define i64 @test14() nounwind {
+entry:
+ %tmp = load i64* bitcast ([2 x i8*]* @g6 to i64*)
+ ret i64 %tmp
+; CHECK: @test14
+; CHECK: ret i64 1
+}
+
+define i64 @test15() nounwind {
+entry:
+ %tmp = load i64* bitcast (i8** getelementptr inbounds ([2 x i8*]* @g6, i32 0, i64 1) to i64*)
+ ret i64 %tmp
+; CHECK: @test15
+; CHECK: ret i64 2
+}