Author: void Date: Tue Oct 2 16:43:06 2007 New Revision: 42552 URL: http://llvm.org/viewvc/llvm-project?rev=42552&view=rev Log: Another missed optimization with LICM.
Modified: llvm/trunk/lib/Target/X86/README.txt Modified: llvm/trunk/lib/Target/X86/README.txt URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/lib/Target/X86/README.txt?rev=42552&r1=42551&r2=42552&view=diff ============================================================================== --- llvm/trunk/lib/Target/X86/README.txt (original) +++ llvm/trunk/lib/Target/X86/README.txt Tue Oct 2 16:43:06 2007 @@ -1283,3 +1283,26 @@ //===---------------------------------------------------------------------===// +For this code: + +cond_next603: ; preds = %bb493, %cond_true336, %cond_next599 + %v.21050.1 = phi i32 [ %v.21050.0, %cond_next599 ], [ %tmp344, %cond_true336 ], [ %v.2, %bb493 ] ; <i32> [#uses=1] + %maxz.21051.1 = phi i32 [ %maxz.21051.0, %cond_next599 ], [ 0, %cond_true336 ], [ %maxz.2, %bb493 ] ; <i32> [#uses=2] + %cnt.01055.1 = phi i32 [ %cnt.01055.0, %cond_next599 ], [ 0, %cond_true336 ], [ %cnt.0, %bb493 ] ; <i32> [#uses=2] + %byteptr.9 = phi i8* [ %byteptr.12, %cond_next599 ], [ %byteptr.0, %cond_true336 ], [ %byteptr.10, %bb493 ] ; <i8*> [#uses=9] + %bitptr.6 = phi i32 [ %tmp5571104.1, %cond_next599 ], [ %tmp4921049, %cond_true336 ], [ %bitptr.7, %bb493 ] ; <i32> [#uses=4] + %source.5 = phi i32 [ %tmp602, %cond_next599 ], [ %source.0, %cond_true336 ], [ %source.6, %bb493 ] ; <i32> [#uses=7] + %tmp606 = getelementptr %struct.const_tables* @tables, i32 0, i32 0, i32 %cnt.01055.1 ; <i8*> [#uses=1] + %tmp607 = load i8* %tmp606, align 1 ; <i8> [#uses=1] + +We produce this: + +LBB4_70: # cond_next603 + movl -20(%ebp), %esi + movl L_tables$non_lazy_ptr-"L4$pb"(%esi), %esi + +However, ICC caches this information before the loop and produces this: + + movl 88(%esp), %eax #481.12 + +//===---------------------------------------------------------------------===// _______________________________________________ llvm-commits mailing list llvm-commits@cs.uiuc.edu http://lists.cs.uiuc.edu/mailman/listinfo/llvm-commits