When a constant's type is refined, update the constant in place

instead of cloning and RAUWing it.

 - Make AbstractTypeUser a friend of Value so that it can offer
   its subclasses a way to update a Value's type in place. This
   is better than a universally visible setType method on Value,
   and it's sufficient for the immediate need.

 - Eliminate the constant "convert" functions. This eliminates a
   lot of logic duplication, and fixes a complicated bug where a
   constant can't actually be cloned during the type refinement
   process because some of the types that its folder needs are
   half-destroyed, being in the middle of refinement themselves.

 - Move the getValType functions from being static overloaded
   functions in Constants.cpp to be members of class template
   specializations in ConstantsContext.h. This means that the
   code ends up getting instantiated twice, however it also
   makes it possible to eliminate all "convert" functions, so
   it's not a big net code size increase. And if desired, the
   duplicate instantiations could be eliminated with some
   reorganization.

llvm-svn: 81861

2 files changed, 44 insertions, 0 deletions

diff --git a/llvm/test/Linker/partial-type-refinement-link.ll b/llvm/test/Linker/partial-type-refinement-link.ll
new file mode 100644
index 00000000000..320ef969f83
--- /dev/null
+++ b/llvm/test/Linker/partial-type-refinement-link.ll
@@ -0,0 +1,20 @@
+; This file is used by first.ll, so it doesn't actually do anything itself
+; RUN: true
+
+%AnalysisResolver = type { i8, %PMDataManager* }
+%"DenseMap<P*,AU*>" = type { i64, %"pair<P*,AU*>"*, i64, i64 }
+%PMDataManager = type { i8, %PMTopLevelManager*, i8, i8, i8, i8, i8, i64, i8 }
+%PMTopLevelManager = type { i8, i8, i8, i8, i8, i8, i8, i8, %"DenseMap<P*,AU*>" }
+%P = type { i8, %AnalysisResolver*, i64 }
+%PI = type { i8, i8, i8, i8, i8, i8, %"vector<const PI*>", %P* }
+%"SmallVImpl<const PI*>" = type { i8, %PI* }
+%"_V_base<const PI*>" = type { %"_V_base<const PI*>::_V_impl" }
+%"_V_base<const PI*>::_V_impl" = type { %PI*, i8, i8 }
+%"pair<P*,AU*>" = type opaque
+%"vector<const PI*>" = type { %"_V_base<const PI*>" }
+
+define void @f(%"SmallVImpl<const PI*>"* %this) {
+entry:
+  %x = getelementptr inbounds %"SmallVImpl<const PI*>"* %this, i64 0, i32 1
+  ret void
+}
diff --git a/llvm/test/Linker/partial-type-refinement.ll b/llvm/test/Linker/partial-type-refinement.ll
new file mode 100644
index 00000000000..b995f11533f
--- /dev/null
+++ b/llvm/test/Linker/partial-type-refinement.ll
@@ -0,0 +1,24 @@
+; RUN: llvm-link %s %p/partial-type-refinement-link.ll -S | FileCheck %s
+; PR4954
+
+; CHECK: load %PI** getelementptr inbounds (%"RegisterP<LowerArrayLength>"* @_ZN3mvmL1XE, i64 0, i32 0, i32 6, i32 0, i32 0, i32 0), align 16
+
+%AnalysisResolver = type { i8, %PMDataManager* }
+%"DenseMap<P*,AU*>" = type { i64, %"pair<P*,AU*>"*, i64, i64 }
+%PMDataManager = type { i8, %PMTopLevelManager*, i8, i8, i8, i8, i8, i64, i8 }
+%PMTopLevelManager = type { i8, i8, i8, i8, i8, i8, i8, i8, %"DenseMap<P*,AU*>" }
+%P = type { i8, %AnalysisResolver*, i64 }
+%PI = type { i8, i8, i8, i8, i8, i8, %"vector<const PI*>", %P* }
+%"RegisterP<LowerArrayLength>" = type { %PI }
+%"_V_base<const PI*>" = type { %"_V_base<const PI*>::_V_impl" }
+%"_V_base<const PI*>::_V_impl" = type { %PI*, i8, i8 }
+%"pair<P*,AU*>" = type opaque
+%"vector<const PI*>" = type { %"_V_base<const PI*>" }
+
+@_ZN3mvmL1XE = external global %"RegisterP<LowerArrayLength>"
+
+define void @__tcf_0() nounwind {
+entry:
+  %0 = load %PI** getelementptr inbounds (%"RegisterP<LowerArrayLength>"* @_ZN3mvmL1XE, i64 0, i32 0, i32 6, i32 0, i32 0, i32 0), align 16
+  ret void
+}