[llvm-commits] [llvm] r129693 - in /llvm/trunk: lib/CodeGen/SelectionDAG/FastISel.cpp test/CodeGen/X86/fast-isel-x86-64.ll

[Chris Lattner]

Author: lattner
Date: Mon Apr 18 01:55:51 2011
New Revision: 129693

URL: http://llvm.org/viewvc/llvm-project?rev=129693&view=rev
Log:
fix rdar://9297011 - udiv by power of two causing fast-isel rejects

Modified:
    llvm/trunk/lib/CodeGen/SelectionDAG/FastISel.cpp
    llvm/trunk/test/CodeGen/X86/fast-isel-x86-64.ll

Modified: llvm/trunk/lib/CodeGen/SelectionDAG/FastISel.cpp
URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/lib/CodeGen/SelectionDAG/FastISel.cpp?rev=129693&r1=129692&r2=129693&view=diff
==============================================================================
--- llvm/trunk/lib/CodeGen/SelectionDAG/FastISel.cpp (original)
+++ llvm/trunk/lib/CodeGen/SelectionDAG/FastISel.cpp Mon Apr 18 01:55:51 2011
@@ -990,6 +990,10 @@
   if (Opcode == ISD::MUL && isPowerOf2_64(Imm)) {
     Opcode = ISD::SHL;
     Imm = Log2_64(Imm);
+  } else if (Opcode == ISD::UDIV && isPowerOf2_64(Imm)) {
+    // div x, 8 -> srl x, 3
+    Opcode = ISD::SRL;
+    Imm = Log2_64(Imm);
   }
   
   // Horrible hack (to be removed), check to make sure shift amounts are

Modified: llvm/trunk/test/CodeGen/X86/fast-isel-x86-64.ll
URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/test/CodeGen/X86/fast-isel-x86-64.ll?rev=129693&r1=129692&r2=129693&view=diff
==============================================================================
--- llvm/trunk/test/CodeGen/X86/fast-isel-x86-64.ll (original)
+++ llvm/trunk/test/CodeGen/X86/fast-isel-x86-64.ll Mon Apr 18 01:55:51 2011
@@ -1,4 +1,4 @@
-; RUN: llc < %s  -fast-isel -O0 -regalloc=fast -asm-verbose=0 | FileCheck %s
+; RUN: llc < %s  -fast-isel -O0 -regalloc=fast -asm-verbose=0 -fast-isel-abort | FileCheck %s
 
 target datalayout = "e-p:64:64:64-i1:8:8-i8:8:8-i16:16:16-i32:32:32-i64:64:64-f32:32:32-f64:64:64-v64:64:64-v128:128:128-a0:0:64-s0:64:64-f80:128:128-n8:16:32:64"
 target triple = "x86_64-apple-darwin10.0.0"
@@ -111,3 +111,11 @@
 ; CHECK: test9:
 ; CHECK: imulq	$7, %rdi, %rax
 }
+
+; rdar://9297011 - Don't reject udiv by a power of 2.
+define i32 @test10(i32 %X) nounwind {
+  %Y = udiv i32 %X, 8
+  ret i32 %Y
+; CHECK: test10:
+; CHECK: shrl	$3, 
+}