Implemented global redzones.

tests_lit/asan_tests/globalredzones.ll

+; Test of global redzone layout
+
+; REQUIRES: allow_dump
+
+; RUN: %lc2i -i %s --args -threads=0 -fsanitize-address \

[Karl, 2016/06/13 17:55:50]

nit: %p2i (rather than %lc2i)is a better choice. lc2i is less efficient, and not
as robust.

[tlively, 2016/06/13 18:17:26]

Done.

+; RUN:     | %iflc FileCheck %s
+; RUN: %lc2i -i %s --args -verbose=global_init,inst -threads=0 \

[Karl, 2016/06/13 17:55:49]

Same here.

[tlively, 2016/06/13 18:17:26]

Done.

+; RUN:     -fsanitize-address | %iflc FileCheck --check-prefix=DUMP %s
+
+; DUMP-LABEL: ========= Instrumented Globals =========
+
+; The array of redzones
+; CHECK-LABEL: .type   __$rz0,%object
+; CHECK-NEXT: .section   .rodata
+; CHECK-NEXT: __$rz0:
+; CHECK-NEXT: .long   __$rz2
+; CHECK-NEXT: .long   __$rz3
+; CHECK-NEXT: .long   __$rz4
+; CHECK-NEXT: .long   __$rz5
+; CHECK-NEXT: .long   __$rz6
+; CHECK-NEXT: .long   __$rz7
+; CHECK-LABEL: .type   __$rz1,%object
+; CHECK-NEXT: .section   .rodata
+; CHECK-NEXT: __$rz1:
+; CHECK-NEXT: .byte   6
+; CHECK-NEXT: .byte   0
+; CHECK-NEXT: .byte   0
+; CHECK-NEXT: .byte   0
+; DUMP: @__$rz0 = internal constant <{ i32, i32, i32, i32, i32, i32 }> <{ i32 ptrtoint ([32 x i8]* @__$rz2 to i32), i32 ptrtoint ([32 x i8]* @__$rz3 to i32), i32 ptrtoint ([32 x i8]* @__$rz4 to i32), i32 ptrtoint ([32 x i8]* @__$rz5 to i32), i32 ptrtoint ([32 x i8]* @__$rz6 to i32), i32 ptrtoint ([32 x i8]* @__$rz7 to i32) }> 
+; DUMP-NEXT: @__$rz1 = internal constant [4 x i8] c"\06\00\00\00"                                                                                                 
+; A zero-initialized global
+@zeroInitGlobal = internal global [32 x i8] zeroinitializer
+; CHECK-LABEL: .type   __$rz2,%object
+; CHECK-NEXT: .section   .bss
+; CHECK-NEXT: __$rz2:
+; CHECK-LABEL: .type   zeroInitGlobal,%object
+; CHECK-NEXT: .section   .bss
+; CHECK-NEXT: zeroInitGlobal:
+; CHECK-LABEL: .type   __$rz3,%object
+; CHECK-NEXT: .section   .bss
+; CHECK-NEXT: __$rz3:
+; DUMP-NEXT: @__$rz2 = internal global [32 x i8] zeroinitializer

[Karl, 2016/06/13 17:55:50]

Nit: I think that DUMP-NEXT's should appear first. You may also want to add
spaces between each check.

Also, add a ; DUMP-LABEL: prefix as well (if you need to align for one, why not
the other).

[tlively, 2016/06/13 18:17:26]

Done.

+; DUMP-NEXT: @zeroInitGlobal = internal global [32 x i8] zeroinitializer
+; DUMP-NEXT: @__$rz3 = internal global [32 x i8] zeroinitializer
+
+; A constant-initialized global
+@constInitGlobal = internal constant [32 x i8] c"ABCDEFGHIJKLMNOPQRSTUVWXYZ012345"

[Karl, 2016/06/13 18:22:04]

Note: Considering moving this to the next line (indented).

+; CHECK-LABEL: .type   __$rz4,%object
+; CHECK-NEXT: .section   .rodata
+; CHECK-NEXT: __$rz4:
+; CHECK-LABEL: .type   constInitGlobal,%object
+; CHECK-NEXT: .section   .rodata
+; CHECK-NEXT: constInitGlobal:
+; CHECK-LABEL: .type   __$rz5,%object
+; CHECK-NEXT: .section   .rodata
+; CHECK-NEXT: __$rz5:
+; DUMP-NEXT: @__$rz4 = internal constant [32 x i8] c"RRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRR"
+; DUMP-NEXT: @constInitGlobal = internal constant [32 x i8] c"ABCDEFGHIJKLMNOPQRSTUVWXYZ012345"
+; DUMP-NEXT: @__$rz5 = internal constant [32 x i8] c"RRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRR"
+
+; A regular global
+@regInitGlobal = internal global [32 x i8] c"ABCDEFGHIJKLMNOPQRSTUVWXYZ012345"
+; CHECK-LABEL: .type   __$rz6,%object
+; CHECK-NEXT: .section   .data
+; CHECK-NEXT: __$rz6:
+; CHECK-LABEL: .type   regInitGlobal,%object
+; CHECK-NEXT: .section   .data
+; CHECK-NEXT: regInitGlobal:
+; CHECK-LABEL: .type   __$rz7,%object
+; CHECK-NEXT: .section   .data
+; CHECK-NEXT: __$rz7:
+; DUMP-NEXT: @__$rz6 = internal global [32 x i8] c"RRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRR"
+; DUMP-NEXT: @regInitGlobal = internal global [32 x i8] c"ABCDEFGHIJKLMNOPQRSTUVWXYZ012345"
+; DUMP-NEXT: @__$rz7 = internal global [32 x i8] c"RRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRR"
+
+define internal void @func() {
+  ret void
+}
+
+; CHECK-LABEL: func:
+; DUMP: define internal void @func() {