[llvm-commits] [llvm] r99575 - in /llvm/trunk: lib/CodeGen/SimpleRegisterCoalescing.cpp test/CodeGen/X86/2009-02-26-MachineLICMBug.ll test/CodeGen/X86/phys_subreg_coalesce-2.ll test/CodeGen/X86/pr2659.ll

[Evan Cheng]

Author: evancheng
Date: Thu Mar 25 19:07:25 2010
New Revision: 99575

URL: http://llvm.org/viewvc/llvm-project?rev=99575&view=rev
Log:
Try trivial remat before the coalescer gives up on a vr / physreg coalescing for fear of tying up a physical register.

Modified:
    llvm/trunk/lib/CodeGen/SimpleRegisterCoalescing.cpp
    llvm/trunk/test/CodeGen/X86/2009-02-26-MachineLICMBug.ll
    llvm/trunk/test/CodeGen/X86/phys_subreg_coalesce-2.ll
    llvm/trunk/test/CodeGen/X86/pr2659.ll

Modified: llvm/trunk/lib/CodeGen/SimpleRegisterCoalescing.cpp
URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/lib/CodeGen/SimpleRegisterCoalescing.cpp?rev=99575&r1=99574&r2=99575&view=diff
==============================================================================
--- llvm/trunk/lib/CodeGen/SimpleRegisterCoalescing.cpp (original)
+++ llvm/trunk/lib/CodeGen/SimpleRegisterCoalescing.cpp Thu Mar 25 19:07:25 2010
@@ -1664,7 +1664,8 @@
       if (JoinPInt.ranges.size() > 1000) {
         mri_->setRegAllocationHint(JoinVInt.reg, 0, JoinPReg);
         ++numAborts;
-        DEBUG(dbgs() << "\tPhysical register too complicated, abort!\n");
+        DEBUG(dbgs()
+              << "\tPhysical register live interval too complicated, abort!\n");
         return false;
       }
 
@@ -1675,6 +1676,11 @@
       if (Length > Threshold &&
           (((float)std::distance(mri_->use_nodbg_begin(JoinVReg),
                                  mri_->use_nodbg_end()) / Length) < Ratio)) {
+        // Before giving up coalescing, if definition of source is defined by
+        // trivial computation, try rematerializing it.
+        if (ReMaterializeTrivialDef(SrcInt, DstReg, DstSubIdx, CopyMI))
+          return true;
+
         mri_->setRegAllocationHint(JoinVInt.reg, 0, JoinPReg);
         ++numAborts;
         DEBUG(dbgs() << "\tMay tie down a physical register, abort!\n");

Modified: llvm/trunk/test/CodeGen/X86/2009-02-26-MachineLICMBug.ll
URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/test/CodeGen/X86/2009-02-26-MachineLICMBug.ll?rev=99575&r1=99574&r2=99575&view=diff
==============================================================================
--- llvm/trunk/test/CodeGen/X86/2009-02-26-MachineLICMBug.ll (original)
+++ llvm/trunk/test/CodeGen/X86/2009-02-26-MachineLICMBug.ll Thu Mar 25 19:07:25 2010
@@ -1,5 +1,7 @@
 ; RUN: llc < %s -march=x86-64 -mattr=+sse3 -stats |& grep {2 machine-licm}
+; RUN: llc < %s -march=x86-64 -mattr=+sse3 | FileCheck %s
 ; rdar://6627786
+; rdar://7792037
 
 target triple = "x86_64-apple-darwin10.0"
 	%struct.Key = type { i64 }
@@ -11,6 +13,13 @@
 	br label %bb4
 
 bb4:		; preds = %bb.i, %bb26, %bb4, %entry
+; CHECK: %bb4
+; CHECK: xorb
+; CHECK: callq
+; CHECK: movq
+; CHECK: xorl
+; CHECK: xorb
+
 	%0 = call i32 (...)* @xxGetOffsetForCode(i32 undef) nounwind		; <i32> [#uses=0]
 	%ins = or i64 %p, 2097152		; <i64> [#uses=1]
 	%1 = call i32 (...)* @xxCalculateMidType(%struct.Key* %desc, i32 0) nounwind		; <i32> [#uses=1]

Modified: llvm/trunk/test/CodeGen/X86/phys_subreg_coalesce-2.ll
URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/test/CodeGen/X86/phys_subreg_coalesce-2.ll?rev=99575&r1=99574&r2=99575&view=diff
==============================================================================
--- llvm/trunk/test/CodeGen/X86/phys_subreg_coalesce-2.ll (original)
+++ llvm/trunk/test/CodeGen/X86/phys_subreg_coalesce-2.ll Thu Mar 25 19:07:25 2010
@@ -1,4 +1,4 @@
-; RUN: llc < %s -march=x86 | grep mov | count 6
+; RUN: llc < %s -march=x86 | grep mov | count 5
 ; PR2659
 
 define i32 @binomial(i32 %n, i32 %k) nounwind {

Modified: llvm/trunk/test/CodeGen/X86/pr2659.ll
URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/test/CodeGen/X86/pr2659.ll?rev=99575&r1=99574&r2=99575&view=diff
==============================================================================
--- llvm/trunk/test/CodeGen/X86/pr2659.ll (original)
+++ llvm/trunk/test/CodeGen/X86/pr2659.ll Thu Mar 25 19:07:25 2010
@@ -1,4 +1,5 @@
-; RUN: llc < %s -march=x86 -mtriple=i686-apple-darwin9.4.0 | grep movl | count 6
+; RUN: llc < %s -march=x86 -mtriple=i686-apple-darwin9.4.0 | grep movl | count 5
+; RUN: llc < %s -march=x86 -mtriple=i686-apple-darwin9.4.0 | FileCheck %s
 ; PR2659
 
 target datalayout = "e-p:32:32:32-i1:8:8-i8:8:8-i16:16:16-i32:32:32-i64:32:64-f32:32:32-f64:32:64-v64:64:64-v128:128:128-a0:0:64-f80:128:128"
@@ -13,6 +14,11 @@
   %cmp44 = icmp eq i32 %k, 0            ; <i1> [#uses=1]
   br i1 %cmp44, label %afterfor, label %forbody
 
+; CHECK: %forcond.preheader.forbody_crit_edge
+; CHECK: movl $1
+; CHECK-NOT: xorl
+; CHECK-NEXT: movl $1
+
 ifthen:         ; preds = %entry
   ret i32 0