[IR] Remove support for icmp and fcmp constant expressions (#93038)

Remove support for the icmp and fcmp constant expressions.

This is part of:
https://discourse.llvm.org/t/rfc-remove-most-constant-expressions/63179

As usual, many of the updated tests will no longer test what they were
originally intended to -- this is hard to preserve when constant
expressions get removed, and in many cases just impossible as the
existence of a specific kind of constant expression was the cause of the
issue in the first place.

1 files changed, 2 insertions, 4 deletions

diff --git a/llvm/lib/Bitcode/Reader/BitcodeReader.cpp b/llvm/lib/Bitcode/Reader/BitcodeReader.cpp
index aee627b..8519796 100644
--- a/llvm/lib/Bitcode/Reader/BitcodeReader.cpp
+++ b/llvm/lib/Bitcode/Reader/BitcodeReader.cpp
@@ -1495,6 +1495,8 @@ static bool isConstExprSupported(const BitcodeConstant *BC) {
   switch (Opcode) {
   case Instruction::FNeg:
   case Instruction::Select:
+  case Instruction::ICmp:
+  case Instruction::FCmp:
     return false;
   default:
     return true;
@@ -1633,10 +1635,6 @@ Expected<Value *> BitcodeReader::materializeValue(unsigned StartValID,
         case BitcodeConstant::ConstantVectorOpcode:
           C = ConstantVector::get(ConstOps);
           break;
-        case Instruction::ICmp:
-        case Instruction::FCmp:
-          C = ConstantExpr::getCompare(BC->Flags, ConstOps[0], ConstOps[1]);
-          break;
         case Instruction::GetElementPtr:
           C = ConstantExpr::getGetElementPtr(
               BC->SrcElemTy, ConstOps[0], ArrayRef(ConstOps).drop_front(),