Subzero: Track protos + globals w/out initializers as undef too (not just helper funcs)

tests_lit/llvm2ice_tests/elf_nodata.ll

Index: tests_lit/llvm2ice_tests/elf_nodata.ll
diff --git a/tests_lit/llvm2ice_tests/elf_nodata.ll b/tests_lit/llvm2ice_tests/elf_nodata.ll
new file mode 100644
index 0000000000000000000000000000000000000000..8170676f0588f76bdf1251f74db075e2ed764a53
--- /dev/null
+++ b/tests_lit/llvm2ice_tests/elf_nodata.ll
@@ -0,0 +1,127 @@
+; Tests that we generate an ELF container correctly when there
+; is no data section.
+
+; For the integrated ELF writer, we can't pipe the output because we need
+; to seek backward and patch up the file headers. So, use a temporary file.
+; RUN: %p2i -i %s --args -O2 --verbose none -elf-writer -o %t \
+; RUN:   && llvm-readobj -file-headers -sections -section-data \
+; RUN:       -relocations -symbols %t | FileCheck %s
+
+; RUN: %p2i -i %s --args -O2 --verbose none \
+; RUN:   | llvm-mc -triple=i686-none-nacl -filetype=obj -o - \
+; RUN:   | llvm-readobj -file-headers -sections -section-data \
+; RUN:       -relocations -symbols - | FileCheck %s
+
+declare void @llvm.memcpy.p0i8.p0i8.i32(i8*, i8*, i32, i32, i1)
+
+define internal i32 @foo(i32 %x, i32 %len) {
+  %y = add i32 %x, %x
+  %dst = inttoptr i32 %y to i8*
+  %src = inttoptr i32 %x to i8*
+  call void @llvm.memcpy.p0i8.p0i8.i32(i8* %dst, i8* %src,
+                                       i32 %len, i32 1, i1 false)
+
+  ret i32 %y
+}
+
+; Test defining a non-internal function.
+define void @_start(i32 %x) {
+  %ignored = call i32 @foo(i32 %x, i32 4)
+  ret void
+}
+
+; CHECK:   Section {
+; CHECK:     Index: {{[1-9][0-9]*}}
+; CHECK:     Name: .text
+; CHECK:     Type: SHT_PROGBITS
+; CHECK:     Flags [ (0x6)
+; CHECK:       SHF_ALLOC
+; CHECK:       SHF_EXECINSTR
+; CHECK:     ]
+; CHECK:     Address: 0x0
+; CHECK:     Offset: 0x{{[1-9A-F][0-9A-F]*}}
+; CHECK:     Size: {{[1-9][0-9]*}}
+; CHECK:     Link: 0
+; CHECK:     Info: 0
+; CHECK:     AddressAlignment: 32
+; CHECK:     EntrySize: 0
+; CHECK:     SectionData (
+; CHECK:     )
+; CHECK:   }
+; CHECK:   Section {
+; CHECK:     Index: {{[1-9][0-9]*}}
+; CHECK:     Name: .rel.text
+; CHECK:     Type: SHT_REL
+; CHECK:     Flags [ (0x0)
+; CHECK:     ]
+; CHECK:     Address: 0x0
+; CHECK:     Offset: 0x{{[1-9A-F][0-9A-F]*}}
+; CHECK:     Size: {{[1-9][0-9]*}}
+; CHECK:     Link: [[SYMTAB_INDEX:[1-9][0-9]*]]
+; CHECK:     Info: {{[1-9][0-9]*}}
+; CHECK:     AddressAlignment: 4
+; CHECK:     EntrySize: 8
+; CHECK:     SectionData (
+; CHECK:     )
+; CHECK:   }
+; CHECK:   Section {
+; CHECK:     Index: [[SYMTAB_INDEX]]
+; CHECK-NEXT: Name: .symtab
+; CHECK:     Type: SHT_SYMTAB
+; CHECK:     Flags [ (0x0)
+; CHECK:     ]
+; CHECK:     Address: 0x0
+; CHECK:     Offset: 0x{{[1-9A-F][0-9A-F]*}}
+; CHECK:     Size: {{[1-9][0-9]*}}
+; CHECK:     Link: {{[1-9][0-9]*}}
+; CHECK:     Info: {{[1-9][0-9]*}}
+; CHECK:     AddressAlignment: 4
+; CHECK:     EntrySize: 16
+; CHECK:   }
+
+
+; CHECK: Relocations [
+; CHECK:   Section ({{[0-9]+}}) .rel.text {
+; CHECK:     0x21 R_386_PC32 memcpy 0x0
+; CHECK:   }
+; CHECK: ]
+
+
+; CHECK: Symbols [
+; CHECK-NEXT:   Symbol {
+; CHECK-NEXT:     Name: (0)
+; CHECK-NEXT:     Value: 0x0
+; CHECK-NEXT:     Size: 0
+; CHECK-NEXT:     Binding: Local
+; CHECK-NEXT:     Type: None
+; CHECK-NEXT:     Other: 0
+; CHECK-NEXT:     Section: Undefined (0x0)
+; CHECK-NEXT:   }
+; CHECK:        Symbol {
+; CHECK:          Name: foo
+; CHECK-NEXT:     Value: 0x0
+; CHECK-NEXT:     Size: 0
+; CHECK-NEXT:     Binding: Local
+; CHECK-NEXT:     Type: None
+; CHECK-NEXT:     Other: 0
+; CHECK-NEXT:     Section: .text
+; CHECK-NEXT:   }
+; CHECK:        Symbol {
+; CHECK:          Name: _start
+; CHECK-NEXT:     Value: 0x{{[1-9A-F][0-9A-F]*}}
+; CHECK-NEXT:     Size: 0
+; CHECK-NEXT:     Binding: Global
+; CHECK-NEXT:     Type: Function
+; CHECK-NEXT:     Other: 0
+; CHECK-NEXT:     Section: .text
+; CHECK-NEXT:   }
+; CHECK:        Symbol {
+; CHECK:          Name: memcpy
+; CHECK-NEXT:     Value: 0x0
+; CHECK-NEXT:     Size: 0
+; CHECK-NEXT:     Binding: Global
+; CHECK-NEXT:     Type: None
+; CHECK-NEXT:     Other: 0
+; CHECK-NEXT:     Section: Undefined
+; CHECK-NEXT:   }
+; CHECK: ]