[clang] [llvm] [RISCV] Xqccmp Code Generation (PR #128815)

[Sam Elliott via llvm-commits]

================
@@ -783,6 +783,54 @@ void RISCVFrameLowering::allocateStack(MachineBasicBlock &MBB,
   }
 }
 
+static bool isPush(unsigned Opcode) {
+  switch (Opcode) {
+  case RISCV::CM_PUSH:
+  case RISCV::QC_CM_PUSH:
+  case RISCV::QC_CM_PUSHFP:
+    return true;
+  default:
+    return false;
+  }
+}
+
+static bool isPop(unsigned Opcode) {
+  // There are other pops but these are the only ones introduced during this
+  // pass.
+  switch (Opcode) {
+  case RISCV::CM_POP:
+  case RISCV::QC_CM_POP:
+    return true;
+  default:
+    return false;
+  }
+}
+
+static unsigned getPushOpcode(RISCVMachineFunctionInfo::PushKind Kind,
+                              bool hasFP) {
+  switch (Kind) {
+  case RISCVMachineFunctionInfo::PushKind::StdExtZcmp:
+    return RISCV::CM_PUSH;
+  case RISCVMachineFunctionInfo::PushKind::VendorXqccmp:
+    return hasFP ? RISCV::QC_CM_PUSHFP : RISCV::QC_CM_PUSH;
+  default:
+    llvm_unreachable("Unhandled PushKind");
+  }
+}
+
+static unsigned getPopOpcode(RISCVMachineFunctionInfo::PushKind Kind) {
+  // There are other pops but they are introduced later by the Push/Pop
+  // Optimizer.
+  switch (Kind) {
+  case RISCVMachineFunctionInfo::PushKind::StdExtZcmp:
+    return RISCV::CM_POP;
+  case llvm::RISCVMachineFunctionInfo::PushKind::VendorXqccmp:
+    return RISCV::CM_POP;
+  default:
+    llvm_unreachable("Unhandled Push Kind");
----------------
lenary wrote:

I used "Push Kind" to echo the enum name, but now I think I shall call the enum PushPopKind to make it clearer that it applies to both.

https://github.com/llvm/llvm-project/pull/128815