Skip to content

[CIR] Added codegen support for builtin_mempcpy #1844

New issue

Have a question about this project? Sign up for a free GitHub account to open an issue and contact its maintainers and the community.

Sign up for GitHub

By clicking “Sign up for GitHub”, you agree to our terms of service and privacy statement. We’ll occasionally send you account related emails.

Already on GitHub? Sign in to your account

Merged
merged 3 commits into from
Aug 22, 2025
Merged

[CIR] Added codegen support for builtin_mempcpy #1844

Show file tree
Hide file tree
Changes from 1 commit
Commits
Show all changes
3 commits
Select commit Hold shift + click to select a range
b2324bc
[CIR] Added codegen support for builtin_mempcpy
badumbatish Aug 20, 2025
c5f91e2
Resolve PR reviews, add extra checks for future
badumbatish Aug 20, 2025
9ec883b
Stricter SSA check for test, resolve PR comments
badumbatish Aug 21, 2025
File filter

Filter by extension

Filter by extension
Conversations
Failed to load comments.
Loading
Jump to
Jump to file
Failed to load files.
Loading
Diff view
Diff view
12 changes: 8 additions & 4 deletions clang/lib/CIR/CodeGen/CIRGenBuiltin.cpp
View file
Open in desktop
Original file line number Diff line number Diff line change
Expand Up @@ -1687,10 +1687,14 @@ RValue CIRGenFunction::emitBuiltinExpr(const GlobalDecl GD, unsigned BuiltinID,
builder.createMemCpy(getLoc(E->getSourceRange()), Dest.getPointer(),
Src.getPointer(), SizeVal);
if (BuiltinID == Builtin::BImempcpy ||
BuiltinID == Builtin::BI__builtin_mempcpy)
llvm_unreachable("mempcpy is NYI");
else
return RValue::get(Dest.getPointer());
BuiltinID == Builtin::BI__builtin_mempcpy) {
auto ppTy = builder.getPointerTo(builder.getUInt8PtrTy());
auto castBuf = builder.createBitcast(Dest.getPointer(), ppTy);
auto loc = getLoc(E->getSourceRange());
auto gep = cir::PtrStrideOp::create(builder, loc, ppTy, castBuf, SizeVal);
return RValue::get(gep);
}
return RValue::get(Dest.getPointer());
}

case Builtin::BI__builtin_memcpy_inline: {
Expand Down
18 changes: 18 additions & 0 deletions clang/test/CIR/CodeGen/builtins-memory.c
View file
Open in desktop
Original file line number Diff line number Diff line change
Expand Up @@ -230,3 +230,21 @@ void test_memset_inline(void *dst, int val) {
// LLVM: call void @llvm.memset.inline.p0.i64(ptr {{%.*}}, i8 {{%.*}}, i64 4, i1 false)
__builtin_memset_inline(dst, val, 4);
}

void* test_builtin_mempcpy(void *dest, void *src, size_t n) {

// CIR-LABEL: test_builtin_mempcpy
// CIR: cir.libc.memcpy {{%.*}} bytes from {{%.*}} to {{%.*}} : !u64i, !cir.ptr<!void> -> !cir.ptr<!void>
// CIR: cir.store [[GEP:%.*]], [[P:%.*]]
// CIR: [[LD:%.*]] = cir.load [[P:%.*]]
// CIR: cir.return [[LD]]


// LLVM-LABEL: test_builtin_mempcpy
// LLVM: call void @llvm.memcpy.p0.p0.i64(ptr {{%.*}}, ptr {{%.*}}, i64 {{%.*}}, i1 false)
// LLVM: [[GEP:%.*]] = getelementptr
// LLVM: store ptr [[GEP]], ptr [[P:%.*]]
// LLVM: [[LD:%.*]] = load ptr, ptr [[P]]
// LLVM: ret ptr [[LD]]
return __builtin_mempcpy(dest, src, n);
}
Loading