[CaptureTracking] Support operand bundles conservatively

Summary:
Earlier CaptureTracking would assume all "interesting" operands to a
call or invoke were its arguments.  With operand bundles this is no
longer true.

Note: an earlier change got `doesNotCapture` working correctly with
operand bundles.

This change uses DSE to test the changes to CaptureTracking.  DSE is a
vehicle for testing only, and is not directly involved in this change.

Reviewers: reames, majnemer

Subscribers: llvm-commits

Differential Revision: http://reviews.llvm.org/D14306

llvm-svn: 252095

1 files changed, 29 insertions, 0 deletions

diff --git a/llvm/test/Feature/OperandBundles/dse.ll b/llvm/test/Feature/OperandBundles/dse.ll
new file mode 100644
index 00000000000..cc5647a2fa0
--- /dev/null
+++ b/llvm/test/Feature/OperandBundles/dse.ll
@@ -0,0 +1,29 @@
+; RUN: opt -S -dse < %s | FileCheck %s
+
+declare void @f()
+declare noalias i8* @malloc(i32) nounwind
+
+define void @test_0() {
+; CHECK-LABEL: @test_0(
+  %m = call i8* @malloc(i32 24)
+  tail call void @f() [ "unknown"(i8* %m) ]
+; CHECK: store i8 -19, i8* %m
+  store i8 -19, i8* %m
+  ret void
+}
+
+define i8* @test_1() {
+; CHECK-LABEL: @test_1(
+  %m = call i8* @malloc(i32 24)
+  tail call void @f() [ "unknown"(i8* %m) ]
+  store i8 -19, i8* %m
+  tail call void @f()
+  store i8 101, i8* %m
+
+; CHECK: tail call void @f() [ "unknown"(i8* %m) ]
+; CHECK: store i8 -19, i8* %m
+; CHECK: tail call void @f()
+; CHECK: store i8 101, i8* %m
+
+  ret i8* %m
+}