Adding tests for DebugIR pass
- lit tests verify that each line of input LLVM IR gets a !dbg node and a
  corresponding entry of metadata that contains the line number 
- unit tests verify that DebugIR works as advertised in the interface
- refactored some useful IR generation functionality from the MCJIT unit tests
  so it can be reused

llvm-svn: 185212
diff --git a/llvm/test/Transforms/DebugIR/simple.ll b/llvm/test/Transforms/DebugIR/simple.ll
new file mode 100644
index 0000000..3b18895
--- /dev/null
+++ b/llvm/test/Transforms/DebugIR/simple.ll
@@ -0,0 +1,25 @@
+; ModuleID = 'simple.c'
+target datalayout = "e-p:64:64:64-i1:8:8-i8:8:8-i16:16:16-i32:32:32-i64:64:64-f32:32:32-f64:64:64-v64:64:64-v128:128:128-a0:0:64-s0:64:64-f80:128:128-n8:16:32:64-S128"
+target triple = "x86_64-pc-linux-gnu"
+
+; Function Attrs: nounwind uwtable
+define i32 @main(i32 %argc, i8** %argv) #0 {
+  %1 = alloca i32, align 4                  ; CHECK: !dbg
+  %2 = alloca i32, align 4                  ; CHECK-NEXT: !dbg
+  %3 = alloca i8**, align 8                 ; CHECK-NEXT: !dbg
+  store i32 0, i32* %1                      ; CHECK-NEXT: !dbg
+  store i32 %argc, i32* %2, align 4         ; CHECK-NEXT: !dbg
+  store i8** %argv, i8*** %3, align 8       ; CHECK-NEXT: !dbg
+  %4 = load i32* %2, align 4                ; CHECK-NEXT: !dbg
+  ret i32 %4                                ; CHECK-NEXT: !dbg
+}
+
+attributes #0 = { nounwind uwtable "less-precise-fpmad"="false" "no-frame-pointer-elim"="true" "no-frame-pointer-elim-non-leaf"="true" "no-infs-fp-math"="false" "no-nans-fp-math"="false" "unsafe-fp-math"="false" "use-soft-float"="false" }
+
+; CHECK: = metadata !{i32 10,
+; CHECK-NEXT: = metadata !{i32 11,
+; CHECK-NEXT: = metadata !{i32 12,
+; CHECK-NEXT: = metadata !{i32 13,
+; CHECK-NEXT: = metadata !{i32 14,
+
+; RUN: opt %s -debug-ir -S | FileCheck %s