TableGen: Add MinAlignment predicate

AMDGPU uses some custom code predicates for testing alignments.

I'm still having trouble comprehending the behavior of predicate bits
in the PatFrag hierarchy. Any attempt to abstract these properties
unexpectdly fails to apply them.

llvm-svn: 367373

1 files changed, 18 insertions, 2 deletions

diff --git a/llvm/utils/TableGen/CodeGenDAGPatterns.cpp b/llvm/utils/TableGen/CodeGenDAGPatterns.cpp
index 75890d27..de42365 100644
--- a/llvm/utils/TableGen/CodeGenDAGPatterns.cpp
+++ b/llvm/utils/TableGen/CodeGenDAGPatterns.cpp
@@ -883,7 +883,8 @@ std::string TreePredicateFn::getPredCode() const {
   if (isLoad()) {
     if (!isUnindexed() && !isNonExtLoad() && !isAnyExtLoad() &&
         !isSignExtLoad() && !isZeroExtLoad() && getMemoryVT() == nullptr &&
-        getScalarMemoryVT() == nullptr)
+        getScalarMemoryVT() == nullptr && getAddressSpaces() == nullptr &&
+        getMinAlignment() < 1)
       PrintFatalError(getOrigPatFragRecord()->getRecord()->getLoc(),
                       "IsLoad cannot be used by itself");
   } else {
@@ -903,7 +904,8 @@ std::string TreePredicateFn::getPredCode() const {
 
   if (isStore()) {
     if (!isUnindexed() && !isTruncStore() && !isNonTruncStore() &&
-        getMemoryVT() == nullptr && getScalarMemoryVT() == nullptr)
+        getMemoryVT() == nullptr && getScalarMemoryVT() == nullptr &&
+        getAddressSpaces() == nullptr && getMinAlignment() < 1)
       PrintFatalError(getOrigPatFragRecord()->getRecord()->getLoc(),
                       "IsStore cannot be used by itself");
   } else {
@@ -977,6 +979,13 @@ std::string TreePredicateFn::getPredCode() const {
       Code += ")\nreturn false;\n";
     }
 
+    int64_t MinAlign = getMinAlignment();
+    if (MinAlign > 0) {
+      Code += "if (cast<MemSDNode>(N)->getAlignment() < ";
+      Code += utostr(MinAlign);
+      Code += ")\nreturn false;\n";
+    }
+
     Record *MemoryVT = getMemoryVT();
 
     if (MemoryVT)
@@ -1177,6 +1186,13 @@ ListInit *TreePredicateFn::getAddressSpaces() const {
   return R->getValueAsListInit("AddressSpaces");
 }
 
+int64_t TreePredicateFn::getMinAlignment() const {
+  Record *R = getOrigPatFragRecord()->getRecord();
+  if (R->isValueUnset("MinAlignment"))
+    return 0;
+  return R->getValueAsInt("MinAlignment");
+}
+
 Record *TreePredicateFn::getScalarMemoryVT() const {
   Record *R = getOrigPatFragRecord()->getRecord();
   if (R->isValueUnset("ScalarMemoryVT"))