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-rw-r--r--docs/GetElementPtr.rst34
1 files changed, 17 insertions, 17 deletions
diff --git a/docs/GetElementPtr.rst b/docs/GetElementPtr.rst
index 91025d8..c9cfae6 100644
--- a/docs/GetElementPtr.rst
+++ b/docs/GetElementPtr.rst
@@ -89,12 +89,12 @@ looks like:
void %munge(%struct.munger_struct* %P) {
entry:
- %tmp = getelementptr %struct.munger_struct* %P, i32 1, i32 0
+ %tmp = getelementptr %struct.munger_struct, %struct.munger_struct* %P, i32 1, i32 0
%tmp = load i32* %tmp
- %tmp6 = getelementptr %struct.munger_struct* %P, i32 2, i32 1
+ %tmp6 = getelementptr %struct.munger_struct, %struct.munger_struct* %P, i32 2, i32 1
%tmp7 = load i32* %tmp6
%tmp8 = add i32 %tmp7, %tmp
- %tmp9 = getelementptr %struct.munger_struct* %P, i32 0, i32 0
+ %tmp9 = getelementptr %struct.munger_struct, %struct.munger_struct* %P, i32 0, i32 0
store i32 %tmp8, i32* %tmp9
ret void
}
@@ -109,9 +109,9 @@ To make this clear, let's consider a more obtuse example:
%MyVar = uninitialized global i32
...
- %idx1 = getelementptr i32* %MyVar, i64 0
- %idx2 = getelementptr i32* %MyVar, i64 1
- %idx3 = getelementptr i32* %MyVar, i64 2
+ %idx1 = getelementptr i32, i32* %MyVar, i64 0
+ %idx2 = getelementptr i32, i32* %MyVar, i64 1
+ %idx3 = getelementptr i32, i32* %MyVar, i64 2
These GEP instructions are simply making address computations from the base
address of ``MyVar``. They compute, as follows (using C syntax):
@@ -146,7 +146,7 @@ variable which is always a pointer type. For example, consider this:
%MyStruct = uninitialized global { float*, i32 }
...
- %idx = getelementptr { float*, i32 }* %MyStruct, i64 0, i32 1
+ %idx = getelementptr { float*, i32 }, { float*, i32 }* %MyStruct, i64 0, i32 1
The GEP above yields an ``i32*`` by indexing the ``i32`` typed field of the
structure ``%MyStruct``. When people first look at it, they wonder why the ``i64
@@ -182,7 +182,7 @@ only involved in the computation of addresses. For example, consider this:
%MyVar = uninitialized global { [40 x i32 ]* }
...
- %idx = getelementptr { [40 x i32]* }* %MyVar, i64 0, i32 0, i64 0, i64 17
+ %idx = getelementptr { [40 x i32]* }, { [40 x i32]* }* %MyVar, i64 0, i32 0, i64 0, i64 17
In this example, we have a global variable, ``%MyVar`` that is a pointer to a
structure containing a pointer to an array of 40 ints. The GEP instruction seems
@@ -197,9 +197,9 @@ following:
.. code-block:: llvm
- %idx = getelementptr { [40 x i32]* }* %, i64 0, i32 0
+ %idx = getelementptr { [40 x i32]* }, { [40 x i32]* }* %, i64 0, i32 0
%arr = load [40 x i32]** %idx
- %idx = getelementptr [40 x i32]* %arr, i64 0, i64 17
+ %idx = getelementptr [40 x i32], [40 x i32]* %arr, i64 0, i64 17
In this case, we have to load the pointer in the structure with a load
instruction before we can index into the array. If the example was changed to:
@@ -208,7 +208,7 @@ instruction before we can index into the array. If the example was changed to:
%MyVar = uninitialized global { [40 x i32 ] }
...
- %idx = getelementptr { [40 x i32] }*, i64 0, i32 0, i64 17
+ %idx = getelementptr { [40 x i32] }, { [40 x i32] }*, i64 0, i32 0, i64 17
then everything works fine. In this case, the structure does not contain a
pointer and the GEP instruction can index through the global variable, into the
@@ -225,9 +225,9 @@ index. Consider this example:
.. code-block:: llvm
- %MyVar = global { [10 x i32 ] }
- %idx1 = getelementptr { [10 x i32 ] }* %MyVar, i64 0, i32 0, i64 1
- %idx2 = getelementptr { [10 x i32 ] }* %MyVar, i64 1
+ %MyVar = global { [10 x i32] }
+ %idx1 = getelementptr { [10 x i32] }, { [10 x i32] }* %MyVar, i64 0, i32 0, i64 1
+ %idx2 = getelementptr { [10 x i32] }, { [10 x i32] }* %MyVar, i64 1
In this example, ``idx1`` computes the address of the second integer in the
array that is in the structure in ``%MyVar``, that is ``MyVar+4``. The type of
@@ -248,9 +248,9 @@ type. Consider this example:
.. code-block:: llvm
- %MyVar = global { [10 x i32 ] }
- %idx1 = getelementptr { [10 x i32 ] }* %MyVar, i64 1, i32 0, i64 0
- %idx2 = getelementptr { [10 x i32 ] }* %MyVar, i64 1
+ %MyVar = global { [10 x i32] }
+ %idx1 = getelementptr { [10 x i32] }, { [10 x i32] }* %MyVar, i64 1, i32 0, i64 0
+ %idx2 = getelementptr { [10 x i32] }, { [10 x i32] }* %MyVar, i64 1
In this example, the value of ``%idx1`` is ``%MyVar+40`` and its type is
``i32*``. The value of ``%idx2`` is also ``MyVar+40`` but its type is ``{ [10 x