Address feedback nr.1

Author: Alex B

lld/MachO/ConcatOutputSection.h

@@ -72,7 +72,7 @@ class TextOutputSection : public ConcatOutputSection {
   void finalizeContents() override {}
   void finalize() override;
   bool needsThunks() const;
-  const std::vector<ConcatInputSection *> &getThunks() const { return thunks; }
+  ArrayRef<ConcatInputSection *> getThunks() const { return thunks; }
   void writeTo(uint8_t *buf) const override;
 
   static bool classof(const OutputSection *sec) {

lld/MachO/MapFile.cpp

@@ -165,21 +165,13 @@ static uint64_t getSymSizeForMap(Defined *sym) {
 // This approach creates a new (temporary) vector which is not ideal but the
 // ideal approach leads to a lot of code duplication.
 static std::vector<ConcatInputSection *>
-mergeOrderedInputs(const std::vector<ConcatInputSection *> &inputs1,
-                   const std::vector<ConcatInputSection *> &inputs2) {
-  std::vector<ConcatInputSection *> vec;
-  size_t i = 0, ie = inputs1.size();
-  size_t t = 0, te = inputs2.size();
-  while (i < ie || t < te) {
-    while (i < ie &&
-           (t == te || inputs1[i]->outSecOff <= inputs2[t]->outSecOff)) {
-      vec.push_back(inputs1[i++]);
-    }
-    while (t < te &&
-           (i == ie || inputs2[t]->outSecOff < inputs1[i]->outSecOff)) {
-      vec.push_back(inputs2[t++]);
-    }
-  }
+mergeOrderedInputs(ArrayRef<ConcatInputSection *> inputs1,
+                   ArrayRef<ConcatInputSection *> inputs2) {
+  std::vector<ConcatInputSection *> vec(inputs1.size() + inputs2.size());
+  std::merge(inputs1.begin(), inputs1.end(), inputs2.begin(), inputs2.end(),
+             vec.begin(), [](ConcatInputSection *a, ConcatInputSection *b) {
+               return a->outSecOff < b->outSecOff;
+             });
   return vec;
 }
 

lld/test/MachO/arm64-thunks.s

@@ -18,27 +18,34 @@
 # RUN: llvm-objdump --no-print-imm-hex -d --no-show-raw-insn %t/thunk | FileCheck %s
 
 ## Check that the thunks appear in the map file and that everything is sorted by address
-# MAP: [[0x[0-9A-Fa-f]+]] 0x[0-9A-Fa-f]+ \[[0-9]+\] _b
-# MAP: [[0x[0-9A-Fa-f]+]] 0x[0-9A-Fa-f]+ \[[0-9]+\] _c
-# MAP: [[0x[0-9A-Fa-f]+]] 0x[0-9A-Fa-f]+ \[[0-9]+\] _d.thunk.0
-# MAP: [[0x[0-9A-Fa-f]+]] 0x[0-9A-Fa-f]+ \[[0-9]+\] _e.thunk.0
-# MAP: [[0x[0-9A-Fa-f]+]] 0x[0-9A-Fa-f]+ \[[0-9]+\] _f.thunk.0
-# MAP: [[0x[0-9A-Fa-f]+]] 0x[0-9A-Fa-f]+ \[[0-9]+\] _g.thunk.0
-# MAP: [[0x[0-9A-Fa-f]+]] 0x[0-9A-Fa-f]+ \[[0-9]+\] _h.thunk.0
-# MAP: [[0x[0-9A-Fa-f]+]] 0x[0-9A-Fa-f]+ \[[0-9]+\] ___nan.thunk.0
-# MAP: [[0x[0-9A-Fa-f]+]] 0x[0-9A-Fa-f]+ \[[0-9]+\] _d
-# MAP: [[0x[0-9A-Fa-f]+]] 0x[0-9A-Fa-f]+ \[[0-9]+\] _e
-# MAP: [[0x[0-9A-Fa-f]+]] 0x[0-9A-Fa-f]+ \[[0-9]+\] _f
-# MAP: [[0x[0-9A-Fa-f]+]] 0x[0-9A-Fa-f]+ \[[0-9]+\] _g
-# MAP: [[0x[0-9A-Fa-f]+]] 0x[0-9A-Fa-f]+ \[[0-9]+\] _a.thunk.0
-# MAP: [[0x[0-9A-Fa-f]+]] 0x[0-9A-Fa-f]+ \[[0-9]+\] _b.thunk.0
-# MAP: [[0x[0-9A-Fa-f]+]] 0x[0-9A-Fa-f]+ \[[0-9]+\] _h
-# MAP: [[0x[0-9A-Fa-f]+]] 0x[0-9A-Fa-f]+ \[[0-9]+\] _main
-# MAP: [[0x[0-9A-Fa-f]+]] 0x[0-9A-Fa-f]+ \[[0-9]+\] _c.thunk.0
-# MAP: [[0x[0-9A-Fa-f]+]] 0x[0-9A-Fa-f]+ \[[0-9]+\] _d.thunk.1
-# MAP: [[0x[0-9A-Fa-f]+]] 0x[0-9A-Fa-f]+ \[[0-9]+\] _e.thunk.1
-# MAP: [[0x[0-9A-Fa-f]+]] 0x[0-9A-Fa-f]+ \[[0-9]+\] _f.thunk.1
-# MAP: [[0x[0-9A-Fa-f]+]] 0x[0-9A-Fa-f]+ \[[0-9]+\] _z
+# Because of the `.space` instructions, there will end up being a lot of dead symbols in the linker map
+# so generate a version of the linker map without dead symbols.
+# RUN: awk '/# Dead Stripped Symbols:/ {exit} {print}' %t/thunk.map > %t/thunk_no_dead_syms.map
+
+# RUN: FileCheck %s --input-file %t/thunk_no_dead_syms.map --check-prefix=MAP
+ 
+# MAP:      [[ADDR1:0x[0-9A-Fa-f]+]] {{.*}} _b
+# MAP-NEXT: [[ADDR2:0x[0-9A-Fa-f]+]] {{.*}} _c
+# MAP-NEXT: [[ADDR3:0x[0-9A-Fa-f]+]] {{.*}} _d.thunk.0
+# MAP-NEXT: [[ADDR4:0x[0-9A-Fa-f]+]] {{.*}} _e.thunk.0
+# MAP-NEXT: [[ADDR5:0x[0-9A-Fa-f]+]] {{.*}} _f.thunk.0
+# MAP-NEXT: [[ADDR6:0x[0-9A-Fa-f]+]] {{.*}} _g.thunk.0
+# MAP-NEXT: [[ADDR7:0x[0-9A-Fa-f]+]] {{.*}} _h.thunk.0
+# MAP-NEXT: [[ADDR8:0x[0-9A-Fa-f]+]] {{.*}} ___nan.thunk.0
+# MAP-NEXT: [[ADDR9:0x[0-9A-Fa-f]+]] {{.*}} _d
+# MAP-NEXT: [[ADDR10:0x[0-9A-Fa-f]+]] {{.*}} _e
+# MAP-NEXT: [[ADDR11:0x[0-9A-Fa-f]+]] {{.*}} _f
+# MAP-NEXT: [[ADDR12:0x[0-9A-Fa-f]+]] {{.*}} _g
+# MAP-NEXT: [[ADDR13:0x[0-9A-Fa-f]+]] {{.*}} _a.thunk.0
+# MAP-NEXT: [[ADDR14:0x[0-9A-Fa-f]+]] {{.*}} _b.thunk.0
+# MAP-NEXT: [[ADDR15:0x[0-9A-Fa-f]+]] {{.*}} _h
+# MAP-NEXT: [[ADDR16:0x[0-9A-Fa-f]+]] {{.*}} _main
+# MAP-NEXT: [[ADDR17:0x[0-9A-Fa-f]+]] {{.*}} _c.thunk.0
+# MAP-NEXT: [[ADDR18:0x[0-9A-Fa-f]+]] {{.*}} _d.thunk.1
+# MAP-NEXT: [[ADDR19:0x[0-9A-Fa-f]+]] {{.*}} _e.thunk.1
+# MAP-NEXT: [[ADDR20:0x[0-9A-Fa-f]+]] {{.*}} _f.thunk.1
+# MAP-NEXT: [[ADDR21:0x[0-9A-Fa-f]+]] {{.*}} _z
+
 
 # CHECK: Disassembly of section __TEXT,__text: