[clang] d2f4b7d - Use enum comparison instead of generated switch/case, NFC

[Reid Kleckner via cfe-commits]

Author: Reid Kleckner
Date: 2021-05-13T20:26:50-07:00
New Revision: d2f4b7d77828dba831f4b7429a7c970d71eb853b

URL: https://github.com/llvm/llvm-project/commit/d2f4b7d77828dba831f4b7429a7c970d71eb853b
DIFF: https://github.com/llvm/llvm-project/commit/d2f4b7d77828dba831f4b7429a7c970d71eb853b.diff

LOG: Use enum comparison instead of generated switch/case, NFC

Clang's coverage data for auto-generated switch cases is really, really
large. Before this change, when I enable code coverage, SemaDeclAttr.obj
is 4.0GB. Naturally, this fails to link.

Replacing the RISCV builtin id check with a comparison reduces object
file size from 4.0GB to 330MB. Replacing the AArch64 SVE range check
reduces the size again down to 17MB, which is reasonable.

I think the RISCV switch is larger in coverage data because it uses more
levels of macro expansion, while the SVE intrinsics only use one. In any
case, please try to avoid switches with 1000+ cases, they usually don't
optimize well.

Added: 
    

Modified: 
    clang/lib/Sema/SemaDeclAttr.cpp

Removed: 
    


################################################################################
diff  --git a/clang/lib/Sema/SemaDeclAttr.cpp b/clang/lib/Sema/SemaDeclAttr.cpp
index 72868224cf539..c470598ef4f84 100644
--- a/clang/lib/Sema/SemaDeclAttr.cpp
+++ b/clang/lib/Sema/SemaDeclAttr.cpp
@@ -5133,15 +5133,8 @@ static bool ArmCdeAliasValid(unsigned BuiltinID, StringRef AliasName) {
 }
 
 static bool ArmSveAliasValid(unsigned BuiltinID, StringRef AliasName) {
-  switch (BuiltinID) {
-  default:
-    return false;
-#define GET_SVE_BUILTINS
-#define BUILTIN(name, types, attr) case SVE::BI##name:
-#include "clang/Basic/arm_sve_builtins.inc"
-#undef BUILTIN
-    return true;
-  }
+  return BuiltinID >= AArch64::FirstSVEBuiltin &&
+         BuiltinID <= AArch64::LastSVEBuiltin;
 }
 
 static void handleArmBuiltinAliasAttr(Sema &S, Decl *D, const ParsedAttr &AL) {
@@ -5167,14 +5160,8 @@ static void handleArmBuiltinAliasAttr(Sema &S, Decl *D, const ParsedAttr &AL) {
 }
 
 static bool RISCVAliasValid(unsigned BuiltinID, StringRef AliasName) {
-  switch (BuiltinID) {
-  default:
-    return false;
-#define BUILTIN(ID, TYPE, ATTRS) case RISCV::BI##ID:
-#include "clang/Basic/BuiltinsRISCV.def"
-#undef BUILTIN
-    return true;
-  }
+  return BuiltinID >= Builtin::FirstTSBuiltin &&
+         BuiltinID < RISCV::LastTSBuiltin;
 }
 
 static void handleBuiltinAliasAttr(Sema &S, Decl *D,