Changes in directory llvm/lib/Target/X86:
README.txt updated: 1.142 -> 1.143 --- Log message: this part implemented. --- Diffs of the changes: (+0 -29) README.txt | 29 ----------------------------- 1 files changed, 29 deletions(-) Index: llvm/lib/Target/X86/README.txt diff -u llvm/lib/Target/X86/README.txt:1.142 llvm/lib/Target/X86/README.txt:1.143 --- llvm/lib/Target/X86/README.txt:1.142 Thu Oct 12 17:01:26 2006 +++ llvm/lib/Target/X86/README.txt Sun Oct 22 16:40:12 2006 @@ -607,35 +607,6 @@ cmp eax, 6 jz label -If we aren't going to do this, we should lower the switch better. We compile -the code to: - -_f: - movl 8(%esp), %eax - movl 4(%esp), %ecx - cmpl $6, %ecx - jl LBB1_4 #entry - jmp LBB1_3 #entry -LBB1_3: #entry - cmpl $6, %ecx - je LBB1_1 #bb - jmp LBB1_2 #UnifiedReturnBlock -LBB1_4: #entry - cmpl $4, %ecx - jne LBB1_2 #UnifiedReturnBlock -LBB1_1: #bb - incl %eax - ret -LBB1_2: #UnifiedReturnBlock - ret - -In the code above, the 'if' is turned into a 'switch' at the mid-level. It -looks like the 'lower to branches' mode could be improved a little here. In -particular, the fall-through to LBB1_3 doesn't need a branch. It would also be -nice to eliminate the redundant "cmp 6", maybe by lowering to a linear sequence -of compares if there are below a certain number of cases (instead of a binary -sequence)? - //===---------------------------------------------------------------------===// GCC's ix86_expand_int_movcc function (in i386.c) has a ton of interesting _______________________________________________ llvm-commits mailing list llvm-commits@cs.uiuc.edu http://lists.cs.uiuc.edu/mailman/listinfo/llvm-commits
