[llvm] 0d1b546 - [TableGen][AsmMatcher] Resolve RegClassByHwMode kinds for all operands

[via llvm-commits]

Author: Alexander Richardson
Date: 2026-08-04T12:57:13-07:00
New Revision: 0d1b54604dac73adc16af15f433ae0c92069fcc2

URL: https://github.com/llvm/llvm-project/commit/0d1b54604dac73adc16af15f433ae0c92069fcc2
DIFF: https://github.com/llvm/llvm-project/commit/0d1b54604dac73adc16af15f433ae0c92069fcc2.diff

LOG: [TableGen][AsmMatcher] Resolve RegClassByHwMode kinds for all operands

validateOperandClass() only remapped a RegClassByHwMode operand kind
when the actual parsed operand was a register. When the operand was
something else entirely (e.g. a bare immediate where a register was
expected), this fell through to the generic "Kind <= MCK_LAST_REGISTER"
diagnostic check, so we end up with a generic Match_InvalidOperand.

No test changes here, but this is needed to avoid diagnostic regressions
with the RVY load/store support (PR #177073).

Pull Request: https://github.com/llvm/llvm-project/pull/213479

Added: 
    

Modified: 
    llvm/test/TableGen/RegClassByHwMode.td
    llvm/utils/TableGen/AsmMatcherEmitter.cpp

Removed: 
    


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diff  --git a/llvm/test/TableGen/RegClassByHwMode.td b/llvm/test/TableGen/RegClassByHwMode.td
index ee1e8a32ed711..a9acc154ad933 100644
--- a/llvm/test/TableGen/RegClassByHwMode.td
+++ b/llvm/test/TableGen/RegClassByHwMode.td
@@ -102,7 +102,7 @@ include "Common/RegClassByHwModeCommon.td"
 
 // ASMMATCHER: switch (Kind) {
 
-// ASMMATCHER: if (Operand.isReg() && Kind > MCK_LAST_REGISTER && Kind <= MCK_LAST_REGCLASS_BY_HWMODE) {
+// ASMMATCHER: if (Kind > MCK_LAST_REGISTER && Kind <= MCK_LAST_REGCLASS_BY_HWMODE) {
 // ASMMATCHER-NEXT:    static constexpr MatchClassKind RegClassByHwModeMatchTable[4][3] = {
 // ASMMATCHER-NEXT:      { // DefaultMode
 // ASMMATCHER-NEXT:        MCK_PtrRegs32, // MyPtrRC

diff  --git a/llvm/utils/TableGen/AsmMatcherEmitter.cpp b/llvm/utils/TableGen/AsmMatcherEmitter.cpp
index 119a3da036d91..96188225c472e 100644
--- a/llvm/utils/TableGen/AsmMatcherEmitter.cpp
+++ b/llvm/utils/TableGen/AsmMatcherEmitter.cpp
@@ -2676,7 +2676,11 @@ static void emitValidateOperandClass(const CodeGenTarget &Target,
   unsigned NumClassesByHwMode = RegClassesByHwMode.size();
 
   if (!RegClassesByHwMode.empty()) {
-    OS << "  if (Operand.isReg() && Kind > MCK_LAST_REGISTER &&"
+    // Resolve RegClassByHwMode kinds to their concrete class regardless of
+    // whether Operand is actually a register, so that the diagnostic
+    // fallback paths below (for both register and non-register operands)
+    // see a concrete class rather than an unresolved by-hwmode one.
+    OS << "  if (Kind > MCK_LAST_REGISTER &&"
           " Kind <= MCK_LAST_REGCLASS_BY_HWMODE) {\n";
 
     const CodeGenHwModes &CGH = Target.getHwModes();