[TTI] Fix getGEPCost() for geps with a single operand.

Previously this would sporadically crash as TargetType
was never initialized. We special-case the single-operand
case returning earlier and trying to mimic the behaviour of
isLegalAddressingMode as closely as possible.

Differential Revision:  https://reviews.llvm.org/D37277

llvm-svn: 312357

1 files changed, 28 insertions, 0 deletions

diff --git a/llvm/test/Transforms/SimplifyCFG/gepcost.ll b/llvm/test/Transforms/SimplifyCFG/gepcost.ll
new file mode 100644
index 00000000000..10751f747e3
--- /dev/null
+++ b/llvm/test/Transforms/SimplifyCFG/gepcost.ll
@@ -0,0 +1,28 @@
+; NOTE: Assertions have been autogenerated by utils/update_test_checks.py
+; RUN: opt < %s -S -simplifycfg | FileCheck %s
+
+target datalayout = "e-m:e-p:32:32-i64:64-v128:64:128-a:0:32-n32-S64"
+target triple = "thumbv7m-none--eabi"
+
+@glob = external unnamed_addr constant [16 x i8]
+
+define void @f() {
+; CHECK-LABEL: @f(
+; CHECK-NEXT:  entr:
+; CHECK-NEXT:    br i1 undef, label [[NEXT:%.*]], label [[EXIT:%.*]]
+; CHECK:       next:
+; CHECK-NEXT:    [[PAT:%.*]] = getelementptr [16 x i8], [16 x i8]* @glob
+; CHECK-NEXT:    br label [[EXIT]]
+; CHECK:       exit:
+; CHECK-NEXT:    ret void
+;
+entr:
+  br i1 undef, label %next, label %exit
+
+next:
+  %pat = getelementptr [16 x i8], [16 x i8]* @glob
+  br label %exit
+
+exit:
+  ret void
+}