[JITLink] Don't under-align zero-fill sections.
If content sections have lower alignment than zero-fill sections then bump the
overall segment alignment to avoid under-aligning the zero-fill sections.
llvm-svn: 370072
diff --git a/llvm/lib/ExecutionEngine/JITLink/JITLinkGeneric.cpp b/llvm/lib/ExecutionEngine/JITLink/JITLinkGeneric.cpp
index 96e074d..877107f 100644
--- a/llvm/lib/ExecutionEngine/JITLink/JITLinkGeneric.cpp
+++ b/llvm/lib/ExecutionEngine/JITLink/JITLinkGeneric.cpp
@@ -238,60 +238,47 @@
// Calculate segment content size.
size_t SegContentSize = 0;
+ uint32_t SegContentAlign = 1;
for (auto &SI : SegLayout.ContentSections) {
assert(!SI.S->atoms_empty() && "Sections in layout must not be empty");
assert(!SI.Atoms.empty() && "Section layouts must not be empty");
// Bump to section alignment before processing atoms.
SegContentSize = alignTo(SegContentSize, SI.S->getAlignment());
+ SegContentAlign = std::max(SegContentAlign, SI.S->getAlignment());
for (auto *DA : SI.Atoms) {
SegContentSize = alignTo(SegContentSize, DA->getAlignment());
SegContentSize += DA->getSize();
+ SegContentAlign = std::max(SegContentAlign, DA->getAlignment());
}
}
- // Get segment content alignment.
- unsigned SegContentAlign = 1;
- if (!SegLayout.ContentSections.empty()) {
- auto &FirstContentSection = SegLayout.ContentSections.front();
- SegContentAlign =
- std::max(FirstContentSection.S->getAlignment(),
- FirstContentSection.Atoms.front()->getAlignment());
- }
-
// Calculate segment zero-fill size.
uint64_t SegZeroFillSize = 0;
+ uint32_t SegZeroFillAlign = 1;
+
for (auto &SI : SegLayout.ZeroFillSections) {
assert(!SI.S->atoms_empty() && "Sections in layout must not be empty");
assert(!SI.Atoms.empty() && "Section layouts must not be empty");
// Bump to section alignment before processing atoms.
SegZeroFillSize = alignTo(SegZeroFillSize, SI.S->getAlignment());
+ SegZeroFillAlign = std::max(SegZeroFillAlign, SI.S->getAlignment());
for (auto *DA : SI.Atoms) {
SegZeroFillSize = alignTo(SegZeroFillSize, DA->getAlignment());
SegZeroFillSize += DA->getSize();
+ SegZeroFillAlign = std::max(SegZeroFillAlign, SI.S->getAlignment());
}
}
- // Calculate segment zero-fill alignment.
- uint32_t SegZeroFillAlign = 1;
-
- if (!SegLayout.ZeroFillSections.empty()) {
- auto &FirstZeroFillSection = SegLayout.ZeroFillSections.front();
- SegZeroFillAlign =
- std::max(FirstZeroFillSection.S->getAlignment(),
- FirstZeroFillSection.Atoms.front()->getAlignment());
- }
-
- if (SegContentSize == 0)
- SegContentAlign = SegZeroFillAlign;
-
- if (SegContentAlign % SegZeroFillAlign != 0)
- return make_error<JITLinkError>("First content atom alignment does not "
- "accommodate first zero-fill atom "
- "alignment");
+ assert(isPowerOf2_32(SegContentAlign) &&
+ "Expected content alignment to be power of 2");
+ assert(isPowerOf2_32(SegZeroFillAlign) &&
+ "Expected zero-fill alignment to be power of 2");
+ // Round content alignment up to segment alignment.
+ SegContentAlign = std::max(SegContentAlign, SegZeroFillAlign);
Segments[Prot] = {SegContentSize, SegContentAlign, SegZeroFillSize,
SegZeroFillAlign};