From 44a57d296910dae6d17888a1bf915e477ba2bdf8 Mon Sep 17 00:00:00 2001
From: Alexandros Lamprineas <alexandros.lamprineas@arm.com>
Date: Sun, 14 Jul 2019 18:32:42 +0000
Subject: [PATCH] [clang][Driver][ARM] Favor -mfpu over default CPU features

When processing the command line options march, mcpu and mfpu, we store
the implied target features on a vector. The change D62998 introduced a
temporary vector, where the processed features get accumulated. When
calling DecodeARMFeaturesFromCPU, which sets the default features for
the specified CPU, we certainly don't want to override the features
that have been explicitly specified on the command line. Therefore, the
default features should appear first in the final vector. This problem
became evident once I added the missing (unhandled) target features in
ARM::getExtensionFeatures.

Differential Revision: https://reviews.llvm.org/D63936

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@366027 91177308-0d34-0410-b5e6-96231b3b80d8
---
 include/llvm/Support/ARMTargetParser.def |  1 +
 lib/Support/ARMTargetParser.cpp          | 30 ++++++------------------------
 unittests/Support/TargetParserTest.cpp   | 15 ++++++++-------
 3 files changed, 15 insertions(+), 31 deletions(-)

diff --git a/include/llvm/Support/ARMTargetParser.def b/include/llvm/Support/ARMTargetParser.def
index 593480f2f18..6e17c8cbfd7 100644
--- a/include/llvm/Support/ARMTargetParser.def
+++ b/include/llvm/Support/ARMTargetParser.def
@@ -148,6 +148,7 @@ ARM_ARCH_EXT_NAME("aes",      ARM::AEK_AES,      "+aes",   "-aes")
 ARM_ARCH_EXT_NAME("dotprod",  ARM::AEK_DOTPROD,  "+dotprod","-dotprod")
 ARM_ARCH_EXT_NAME("dsp",      ARM::AEK_DSP,      "+dsp",   "-dsp")
 ARM_ARCH_EXT_NAME("fp",       ARM::AEK_FP,       nullptr,  nullptr)
+ARM_ARCH_EXT_NAME("fp.dp",    ARM::AEK_FP_DP,    nullptr,  nullptr)
 ARM_ARCH_EXT_NAME("mve",      ARM::AEK_SIMD,     "+mve",   "-mve")
 ARM_ARCH_EXT_NAME("mve.fp",   (ARM::AEK_SIMD | ARM::AEK_FP), "+mve.fp", "-mve.fp")
 ARM_ARCH_EXT_NAME("idiv",     (ARM::AEK_HWDIVARM | ARM::AEK_HWDIVTHUMB), nullptr, nullptr)
diff --git a/lib/Support/ARMTargetParser.cpp b/lib/Support/ARMTargetParser.cpp
index e91b508eefd..27d1e5527be 100644
--- a/lib/Support/ARMTargetParser.cpp
+++ b/lib/Support/ARMTargetParser.cpp
@@ -409,30 +409,12 @@ bool ARM::getExtensionFeatures(unsigned Extensions,
   if (Extensions == AEK_INVALID)
     return false;
 
-  if (Extensions & AEK_CRC)
-    Features.push_back("+crc");
-  else
-    Features.push_back("-crc");
-
-  if (Extensions & AEK_DSP)
-    Features.push_back("+dsp");
-  else
-    Features.push_back("-dsp");
-
-  if (Extensions & AEK_FP16FML)
-    Features.push_back("+fp16fml");
-  else
-    Features.push_back("-fp16fml");
-
-  if (Extensions & AEK_RAS)
-    Features.push_back("+ras");
-  else
-    Features.push_back("-ras");
-
-  if (Extensions & AEK_DOTPROD)
-    Features.push_back("+dotprod");
-  else
-    Features.push_back("-dotprod");
+  for (const auto AE : ARCHExtNames) {
+    if ((Extensions & AE.ID) == AE.ID && AE.Feature)
+      Features.push_back(AE.Feature);
+    else if (AE.NegFeature)
+      Features.push_back(AE.NegFeature);
+  }
 
   return getHWDivFeatures(Extensions, Features);
 }
diff --git a/unittests/Support/TargetParserTest.cpp b/unittests/Support/TargetParserTest.cpp
index b11d9ae7f00..34c7a8a4fd1 100644
--- a/unittests/Support/TargetParserTest.cpp
+++ b/unittests/Support/TargetParserTest.cpp
@@ -571,17 +571,18 @@ TEST(TargetParserTest, ARMFPURestriction) {
 TEST(TargetParserTest, ARMExtensionFeatures) {
   std::map<unsigned, std::vector<StringRef>> Extensions;
 
-  Extensions[ARM::AEK_CRC]        = { "+crc",       "-crc" };
-  Extensions[ARM::AEK_DSP]        = { "+dsp",       "-dsp" };
+  for (auto &Ext : ARM::ARCHExtNames) {
+    if (Ext.Feature && Ext.NegFeature)
+      Extensions[Ext.ID] = { StringRef(Ext.Feature),
+                             StringRef(Ext.NegFeature) };
+  }
+
   Extensions[ARM::AEK_HWDIVARM]   = { "+hwdiv-arm", "-hwdiv-arm" };
   Extensions[ARM::AEK_HWDIVTHUMB] = { "+hwdiv",     "-hwdiv" };
-  Extensions[ARM::AEK_RAS]        = { "+ras",       "-ras" };
-  Extensions[ARM::AEK_FP16FML]    = { "+fp16fml",   "-fp16fml" };
-  Extensions[ARM::AEK_DOTPROD]    = { "+dotprod",   "-dotprod" };
 
   std::vector<StringRef> Features;
 
-  EXPECT_FALSE(AArch64::getExtensionFeatures(ARM::AEK_INVALID, Features));
+  EXPECT_FALSE(ARM::getExtensionFeatures(ARM::AEK_INVALID, Features));
 
   for (auto &E : Extensions) {
     // test +extension
@@ -598,7 +599,7 @@ TEST(TargetParserTest, ARMExtensionFeatures) {
     Found = std::find(std::begin(Features), std::end(Features), E.second.at(1));
     EXPECT_TRUE(Found != std::end(Features));
     EXPECT_TRUE(Extensions.size() == Features.size());
-   }
+  }
 }
 
 TEST(TargetParserTest, ARMFPUFeatures) {
-- 
2.11.0