From: Tim Northover <tnorthover@apple.com>
Date: Mon, 4 May 2015 20:41:51 +0000 (+0000)
Subject: CodeGen: match up correct insertvalue indices when assessing tail calls.
X-Git-Url: http://demsky.eecs.uci.edu/git/?a=commitdiff_plain;h=7f88b179b1eaf6083b54176587fe58f9dbc11189;p=oota-llvm.git

CodeGen: match up correct insertvalue indices when assessing tail calls.

When deciding whether a value comes from the aggregate or inserted value of an
insertvalue instruction, we compare the indices against those of the location
we're interested in. One of the lists needs reversing because the input data is
backwards (so that modifications take place at the end of the SmallVector), but
we were reversing both before leading to incorrect results.

Should fix PR23408

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@236457 91177308-0d34-0410-b5e6-96231b3b80d8
---

diff --git a/lib/CodeGen/Analysis.cpp b/lib/CodeGen/Analysis.cpp
index 8e11fe1c9cf..ac0d40ec3a7 100644
--- a/lib/CodeGen/Analysis.cpp
+++ b/lib/CodeGen/Analysis.cpp
@@ -295,7 +295,8 @@ static const Value *getNoopInput(const Value *V,
     } else if (const InsertValueInst *IVI = dyn_cast<InsertValueInst>(V)) {
       // Value may come from either the aggregate or the scalar
       ArrayRef<unsigned> InsertLoc = IVI->getIndices();
-      if (std::equal(InsertLoc.rbegin(), InsertLoc.rend(),
+      assert(ValLoc.size() >= InsertLoc.size() && "extracting too deeply");
+      if (std::equal(InsertLoc.begin(), InsertLoc.end(),
                      ValLoc.rbegin())) {
         // The type being inserted is a nested sub-type of the aggregate; we
         // have to remove those initial indices to get the location we're
diff --git a/test/CodeGen/AArch64/tail-call.ll b/test/CodeGen/AArch64/tail-call.ll
index 7fb39545a32..700eec77636 100644
--- a/test/CodeGen/AArch64/tail-call.ll
+++ b/test/CodeGen/AArch64/tail-call.ll
@@ -103,3 +103,22 @@ define fastcc void @caller_weak() {
   tail call void @callee_weak()
   ret void
 }
+
+declare { [2 x float] } @get_vec2()
+
+define { [3 x float] } @test_add_elem() {
+; CHECK-LABEL: test_add_elem:
+; CHECK: bl get_vec2
+; CHECK: fmov s2, #1.0
+; CHECK: ret
+
+  %call = tail call { [2 x float] } @get_vec2()
+  %arr = extractvalue { [2 x float] } %call, 0
+  %arr.0 = extractvalue [2 x float] %arr, 0
+  %arr.1 = extractvalue [2 x float] %arr, 1
+
+  %res.0 = insertvalue { [3 x float] } undef, float %arr.0, 0, 0
+  %res.01 = insertvalue { [3 x float] } %res.0, float %arr.1, 0, 1
+  %res.012 = insertvalue { [3 x float] } %res.01, float 1.000000e+00, 0, 2
+  ret { [3 x float] } %res.012
+}