From: Eli Friedman <efriedma@codeaurora.org>
Date: Wed, 19 Dec 2018 22:52:04 +0000 (+0000)
Subject: [CodeGenPrepare] Fix bad IR created by large offset GEP splitting.
X-Git-Url: https://granicus.if.org/sourcecode?a=commitdiff_plain;h=ac0962643bb017e9bbd773a62dcc1a8716d9fc28;p=llvm

[CodeGenPrepare] Fix bad IR created by large offset GEP splitting.

Creating the IR builder, then modifying the CFG, leads to an IRBuilder
where the BB and insertion point are inconsistent, so new instructions
have the wrong parent.

Modified an existing test because the test wasn't covering anything
useful (the "invoke" was not actually an invoke by the time we hit the
code in question).

Differential Revision: https://reviews.llvm.org/D55729



git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@349693 91177308-0d34-0410-b5e6-96231b3b80d8
---

diff --git a/lib/CodeGen/CodeGenPrepare.cpp b/lib/CodeGen/CodeGenPrepare.cpp
index 392e8bc0db4..c35f8666fa3 100644
--- a/lib/CodeGen/CodeGenPrepare.cpp
+++ b/lib/CodeGen/CodeGenPrepare.cpp
@@ -5160,11 +5160,11 @@ bool CodeGenPrepare::splitLargeGEPOffsets() {
       }
 
       // Generate a new GEP to replace the current one.
-      IRBuilder<> Builder(GEP);
+      LLVMContext &Ctx = GEP->getContext();
       Type *IntPtrTy = DL->getIntPtrType(GEP->getType());
       Type *I8PtrTy =
-          Builder.getInt8PtrTy(GEP->getType()->getPointerAddressSpace());
-      Type *I8Ty = Builder.getInt8Ty();
+          Type::getInt8PtrTy(Ctx, GEP->getType()->getPointerAddressSpace());
+      Type *I8Ty = Type::getInt8Ty(Ctx);
 
       if (!NewBaseGEP) {
         // Create a new base if we don't have one yet.  Find the insertion
@@ -5200,6 +5200,7 @@ bool CodeGenPrepare::splitLargeGEPOffsets() {
         NewGEPBases.insert(NewBaseGEP);
       }
 
+      IRBuilder<> Builder(GEP);
       Value *NewGEP = NewBaseGEP;
       if (Offset == BaseOffset) {
         if (GEP->getType() != I8PtrTy)
diff --git a/test/Transforms/CodeGenPrepare/AArch64/large-offset-gep.ll b/test/Transforms/CodeGenPrepare/AArch64/large-offset-gep.ll
index 5cc00b75962..005ea37288c 100644
--- a/test/Transforms/CodeGenPrepare/AArch64/large-offset-gep.ll
+++ b/test/Transforms/CodeGenPrepare/AArch64/large-offset-gep.ll
@@ -88,18 +88,23 @@ while_end:
 }
 
 declare %struct_type* @foo()
+declare void @foo2()
 
 define void @test4(i32 %n) personality i32 (...)* @__FrameHandler {
 ; CHECK-LABEL: test4
 entry:
-  %struct = invoke %struct_type* @foo() to label %while_cond unwind label %cleanup
+  br label %while_cond
 
 while_cond:
   %phi = phi i32 [ 0, %entry ], [ %i, %while_body ]
+  %struct = invoke %struct_type* @foo() to label %while_cond_x unwind label %cleanup
+
+while_cond_x:
 ; CHECK:     mov     w{{[0-9]+}}, #40000
 ; CHECK-NOT: mov     w{{[0-9]+}}, #40004
   %gep0 = getelementptr %struct_type, %struct_type* %struct, i64 0, i32 1
   %gep1 = getelementptr %struct_type, %struct_type* %struct, i64 0, i32 2
+  store i32 0, i32* %gep0
   %cmp = icmp slt i32 %phi, %n
   br i1 %cmp, label %while_body, label %while_end
 
@@ -114,8 +119,10 @@ while_end:
   ret void
 
 cleanup:
-  landingpad { i8*, i32 } cleanup
-  unreachable
+  %x10 = landingpad { i8*, i32 }
+          cleanup
+  call void @foo2()
+  resume { i8*, i32 } %x10
 }
 
 declare i32 @__FrameHandler(...)