[lanai] isBrImm should accept any non-constant immediate.

[jpienaar]

Summary

isBrImm should accept any non-constant immediate. Previously it was only accepting LanaiMCExpr ones which was wrong.

[jpienaar]

Changing to test that uses llvm-mc directly instead of llc.

[majnemer]

LGTM

lib/Target/Lanai/AsmParser/LanaiAsmParser.cpp

 
   bool isToken() const override { return Kind == TOKEN; }
 
   bool isBrImm() {
     if (!isImm())
       return false;
 
     // Constant case
-    if (const MCConstantExpr *ConstExpr = dyn_cast<MCConstantExpr>(Imm.Value)) {
-      int64_t Value = ConstExpr->getValue();
-      // Check if value fits in 25 bits with 2 least significant bits 0.
-      return isShiftedUInt<23, 2>(static_cast<int32_t>(Value));
-    }
-
-    // Symbolic reference expression
-    if (const LanaiMCExpr *SymbolRefExpr = dyn_cast<LanaiMCExpr>(Imm.Value))
-      return SymbolRefExpr->getKind() == LanaiMCExpr::VK_Lanai_None;
-
-    // Binary expression
-    if (const MCBinaryExpr *BinaryExpr = dyn_cast<MCBinaryExpr>(Imm.Value))
-      if (const LanaiMCExpr *SymbolRefExpr =
-              dyn_cast<LanaiMCExpr>(BinaryExpr->getLHS()))
-        return SymbolRefExpr->getKind() == LanaiMCExpr::VK_Lanai_None;
-
-    return false;
+    const MCConstantExpr *MCE = dyn_cast<MCConstantExpr>(Imm.Value);
+    if (!MCE)
+      return true;
+    int64_t Value = MCE->getValue();
+    // Check if value fits in 25 bits with 2 least significant bits 0.
+    return isShiftedUInt<23, 2>(static_cast<int32_t>(Value));
   }
 
   bool isBrTarget() { return isBrImm() || isToken(); }
 
   bool isCallTarget() { return isImm() || isToken(); }
 
   bool isHiImm16() {
     if (!isImm())

test/CodeGen/Lanai/inlineasm-global.ll

+; RUN: llc < %s -march=lanai | FileCheck %s
+
+; CHECK: bt .Ltmp
+; CHECK: Ltmp
+; CHECK-NEXT: bt f
+
+module asm ".globl start"
+module asm "start:"
+module asm "\09 .space 48,0"
+module asm "\09 bt 1f"
+module asm "\09 nop "
+module asm "1: "
+module asm "\09bt f"
+module asm "\09nop"
+
+; Function Attrs: norecurse nounwind readnone
+define void @f() #0 {
+entry:
+  ret void
+}