Segmented stacks: omit __morestack call when there's no frame.

[oota-llvm.git] / lib / Target / X86 / X86.td

diff --git a/lib/Target/X86/X86.td b/lib/Target/X86/X86.td
index 423c2c973d091b2654837560db4313f1d9f3d0cc..6912b579b12c3bc7004eb99b0af83bf863a69745 100644 (file)
--- a/lib/Target/X86/X86.td
+++ b/lib/Target/X86/X86.td
@@ -166,6 +166,8 @@ def FeatureCallRegIndirect : SubtargetFeature<"call-reg-indirect",
                                      "Call register indirect">;
 def FeatureLEAUsesAG : SubtargetFeature<"lea-uses-ag", "LEAUsesAG", "true",
                                    "LEA instruction needs inputs at AG stage">;
+def FeatureSlowLEA : SubtargetFeature<"slow-lea", "SlowLEA", "true",
+                                   "LEA instruction with certain arguments is slow">;
 
 //===----------------------------------------------------------------------===//
 // X86 processors supported.
@@ -195,8 +197,7 @@ def : Proc<"pentium3m",       [FeatureSSE1, FeatureSlowBTMem]>;
 def : Proc<"pentium-m",       [FeatureSSE2, FeatureSlowBTMem]>;
 def : Proc<"pentium4",        [FeatureSSE2]>;
 def : Proc<"pentium4m",       [FeatureSSE2, FeatureSlowBTMem]>;
-def : Proc<"x86-64",          [FeatureSSE2, Feature64Bit, FeatureSlowBTMem,
-                               FeatureFastUAMem]>;
+
 // Intel Core Duo.
 def : ProcessorModel<"yonah", SandyBridgeModel,
                      [FeatureSSE3, FeatureSlowBTMem]>;
@@ -227,6 +228,7 @@ def : ProcessorModel<"slm",  SLMModel, [ProcIntelSLM,
                                FeaturePCLMUL, FeatureAES,
                                FeatureCallRegIndirect,
                                FeaturePRFCHW,
+                               FeatureSlowLEA,
                                FeatureSlowBTMem, FeatureFastUAMem]>;
 // "Arrandale" along with corei3 and corei5
 def : ProcessorModel<"corei7", SandyBridgeModel,
@@ -343,6 +345,20 @@ def : Proc<"winchip2",        [Feature3DNow]>;
 def : Proc<"c3",              [Feature3DNow]>;
 def : Proc<"c3-2",            [FeatureSSE1]>;
 
+// We also provide a generic 64-bit specific x86 processor model which tries to
+// be good for modern chips without enabling instruction set encodings past the
+// basic SSE2 and 64-bit ones. It disables slow things from any mainstream and
+// modern 64-bit x86 chip, and enables features that are generally beneficial.
+// 
+// We currently use the Sandy Bridge model as the default scheduling model as
+// we use it across Nehalem, Westmere, Sandy Bridge, and Ivy Bridge which
+// covers a huge swath of x86 processors. If there are specific scheduling
+// knobs which need to be tuned differently for AMD chips, we might consider
+// forming a common base for them.
+def : ProcessorModel<"x86-64", SandyBridgeModel,
+                     [FeatureSSE2, Feature64Bit, FeatureSlowBTMem,
+                      FeatureFastUAMem]>;
+
 //===----------------------------------------------------------------------===//
 // Register File Description
 //===----------------------------------------------------------------------===//