[llvm] [llvm-objcopy] Add change-section-lma *+/-offset (PR #95431)

[Eleanor Bonnici via llvm-commits]

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@@ -670,6 +670,27 @@ static Error handleArgs(const CommonConfig &Config, const ELFConfig &ELFConfig,
     }
   }
 
+  if (Config.ChangeSectionLMAValAll != 0) {
+    for (Segment &Seg : Obj.segments()) {
+      if (Seg.FileSize > 0) {
+        if (Config.ChangeSectionLMAValAll > 0 &&
+            Seg.PAddr > std::numeric_limits<uint64_t>::max() -
+                            Config.ChangeSectionLMAValAll) {
+          return createStringError(errc::invalid_argument,
+                                   "address 0x" + Twine::utohexstr(Seg.PAddr) +
+                                       " would overflow");
+        } else if (Config.ChangeSectionLMAValAll < 0 &&
+                   Seg.PAddr < std::numeric_limits<uint64_t>::min() -
+                                   Config.ChangeSectionLMAValAll)
+          return createStringError(errc::invalid_argument,
+                                   "address 0x" + Twine::utohexstr(Seg.PAddr) +
+                                       " would underflow");
+        else
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eleanor-arm wrote:

The coding standard actually discourages use of `else` after return, so I've removed it. And I've added braces around the previous `else if` because the control flow is "deeply nested".

https://github.com/llvm/llvm-project/pull/95431