Check that emitted instructions meet their predicates on all targets except ARM, Mips, and X86.

Summary:
* ARM is omitted from this patch because this check appears to expose bugs in this target.
* Mips is omitted from this patch because this check either detects bugs or deliberate
  emission of instructions that don't satisfy their predicates. One deliberate
  use is the SYNC instruction where the version with an operand is correctly
  defined as requiring MIPS32 while the version without an operand is defined
  as an alias of 'SYNC 0' and requires MIPS2.
* X86 is omitted from this patch because it doesn't use the tablegen-erated
  MCCodeEmitter infrastructure.

Patches for ARM and Mips will follow.

Depends on D25617

Reviewers: tstellarAMD, jmolloy

Subscribers: wdng, jmolloy, aemerson, rengolin, arsenm, jyknight, nemanjai, nhaehnle, tstellarAMD, llvm-commits

Differential Revision: https://reviews.llvm.org/D25618

llvm-svn: 287439

1 files changed, 12 insertions, 1 deletions

diff --git a/llvm/lib/Target/AArch64/MCTargetDesc/AArch64MCCodeEmitter.cpp b/llvm/lib/Target/AArch64/MCTargetDesc/AArch64MCCodeEmitter.cpp
index e57d39009ee..f7058cdf237 100644
--- a/llvm/lib/Target/AArch64/MCTargetDesc/AArch64MCCodeEmitter.cpp
+++ b/llvm/lib/Target/AArch64/MCTargetDesc/AArch64MCCodeEmitter.cpp
@@ -35,11 +35,13 @@ namespace {
 
 class AArch64MCCodeEmitter : public MCCodeEmitter {
   MCContext &Ctx;
+  const MCInstrInfo &MCII;
 
   AArch64MCCodeEmitter(const AArch64MCCodeEmitter &); // DO NOT IMPLEMENT
   void operator=(const AArch64MCCodeEmitter &);     // DO NOT IMPLEMENT
 public:
-  AArch64MCCodeEmitter(const MCInstrInfo &mcii, MCContext &ctx) : Ctx(ctx) {}
+  AArch64MCCodeEmitter(const MCInstrInfo &mcii, MCContext &ctx)
+      : Ctx(ctx), MCII(mcii) {}
 
   ~AArch64MCCodeEmitter() override {}
 
@@ -170,6 +172,11 @@ public:
 
   unsigned fixOneOperandFPComparison(const MCInst &MI, unsigned EncodedValue,
                                      const MCSubtargetInfo &STI) const;
+
+private:
+  uint64_t computeAvailableFeatures(const FeatureBitset &FB) const;
+  void verifyInstructionPredicates(const MCInst &MI,
+                                   uint64_t AvailableFeatures) const;
 };
 
 } // end anonymous namespace
@@ -547,6 +554,9 @@ unsigned AArch64MCCodeEmitter::fixMOVZ(const MCInst &MI, unsigned EncodedValue,
 void AArch64MCCodeEmitter::encodeInstruction(const MCInst &MI, raw_ostream &OS,
                                              SmallVectorImpl<MCFixup> &Fixups,
                                              const MCSubtargetInfo &STI) const {
+  verifyInstructionPredicates(MI,
+                              computeAvailableFeatures(STI.getFeatureBits()));
+
   if (MI.getOpcode() == AArch64::TLSDESCCALL) {
     // This is a directive which applies an R_AARCH64_TLSDESC_CALL to the
     // following (BLR) instruction. It doesn't emit any code itself so it
@@ -589,4 +599,5 @@ unsigned AArch64MCCodeEmitter::fixOneOperandFPComparison(
   return EncodedValue;
 }
 
+#define ENABLE_INSTR_PREDICATE_VERIFIER
 #include "AArch64GenMCCodeEmitter.inc"