Disable x87 floating point GRA

* Set the CodeGenerator flag to disable x87 floating point GRA when SSE2 is not being used for floating point. * Minor cleanup in RegisterCandidate around the code that uses the getDisableFloatingPointGRA() query. Signed-off-by: Daryl Maier <maier@ca.ibm.com>
eclipse · Oct 19, 2020 · 89a6afe · 89a6afe
1 parent cd753ab
commit 89a6afe
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Showing 2 changed files with 9 additions and 33 deletions.
diff --git a/compiler/optimizer/RegisterCandidate.cpp b/compiler/optimizer/RegisterCandidate.cpp
@@ -1,5 +1,5 @@
 /*******************************************************************************
- * Copyright (c) 2000, 2019 IBM Corp. and others
+ * Copyright (c) 2000, 2020 IBM Corp. and others
  *
  * This program and the accompanying materials are made available under
  * the terms of the Eclipse Public License 2.0 which accompanies this
@@ -2610,41 +2610,13 @@ TR_RegisterCandidates::assign(TR::Block ** cfgBlocks, int32_t numberOfBlocks, in
 
       if (isFloat)
          {
-           if (debug("disableGlobalFPRs")
-               || cg->getDisableFloatingPointGRA()
+         if (cg->getDisableFloatingPointGRA()
 #ifdef J9_PROJECT_SPECIFIC
-               || (dt == TR::DecimalLongDouble)
+             || (dt == TR::DecimalLongDouble)
 #endif
-               )
-              {
-              continue;
-              }
-
-         // Cannot keep FP values on FP stack across a switch on IA32
-         //
-         if (!comp()->cg()->getSupportsJavaFloatSemantics())
-            {
-            temp = rc->getBlocksLiveOnEntry();
-            temp |= rc->getBlocksLiveOnExit();
-            temp &= switchBlocks;
-            if (!temp.isEmpty())
-               {
-               //printf("Discarding FP candidate in %s\n", comp()->getCurrentMethod()->signature());
-               continue;
-               }
-            }
-
-         if (0 && comp()->cg()->spillsFPRegistersAcrossCalls())
+            )
             {
-            temp = rc->getBlocksLiveOnEntry();
-            temp &= rc->getBlocksLiveOnExit();
-            temp &= callBlocks;
-            if (!temp.isEmpty())
-               {
-               //dumpOptDetails(comp(), "Discarding FP candidate %d\n", rc->getSymbolReference()->getReferenceNumber());
-               //printf("Discarding FP candidate in %s\n", comp()->getCurrentMethod()->signature());
-               continue;
-               }
+            continue;
             }
 
          firstRegister = cg->getFirstGlobalFPR(), lastRegister = cg->getLastGlobalFPR();

diff --git a/compiler/x/codegen/OMRCodeGenerator.cpp b/compiler/x/codegen/OMRCodeGenerator.cpp
@@ -268,6 +268,10 @@ OMR::X86::CodeGenerator::initializeX86(TR::Compilation *comp)
       self()->setSupportsAutoSIMD();
       self()->setSupportsJavaFloatSemantics();
       }
+   else
+      {
+      self()->setDisableFloatingPointGRA();
+      }
 
    // Choose the best XMM double precision load instruction for the target architecture.
    //