[Core] Skip over target name in intrinsic name lookup (#109971)

When searching for an intrinsic name in a target specific slice of the
intrinsic name table, skip over the target prefix. For such cases,
currently the first loop iteration in `lookupLLVMIntrinsicByName` does
nothing (i.e., `Low` and `High` stay unchanged and it does not shrink
down the search window), so we can skip this useless first iteration by
skipping over the target prefix.

1 files changed, 6 insertions, 1 deletions

diff --git a/llvm/lib/IR/IntrinsicInst.cpp b/llvm/lib/IR/IntrinsicInst.cpp
index 7ed82c2..5654a3a 100644
--- a/llvm/lib/IR/IntrinsicInst.cpp
+++ b/llvm/lib/IR/IntrinsicInst.cpp
@@ -237,8 +237,10 @@ void DbgAssignIntrinsic::setValue(Value *V) {
 }
 
 int llvm::Intrinsic::lookupLLVMIntrinsicByName(ArrayRef<const char *> NameTable,
-                                               StringRef Name) {
+                                               StringRef Name,
+                                               StringRef Target) {
   assert(Name.starts_with("llvm.") && "Unexpected intrinsic prefix");
+  assert(Name.drop_front(5).starts_with(Target) && "Unexpected target");
 
   // Do successive binary searches of the dotted name components. For
   // "llvm.gc.experimental.statepoint.p1i8.p1i32", we will find the range of
@@ -248,6 +250,9 @@ int llvm::Intrinsic::lookupLLVMIntrinsicByName(ArrayRef<const char *> NameTable,
   // identical. By using strncmp we consider names with differing suffixes to
   // be part of the equal range.
   size_t CmpEnd = 4; // Skip the "llvm" component.
+  if (!Target.empty())
+    CmpEnd += 1 + Target.size(); // skip the .target component.
+
   const char *const *Low = NameTable.begin();
   const char *const *High = NameTable.end();
   const char *const *LastLow = Low;