Changes in directory llvm/lib/CodeGen:
README.txt added (r1.1) --- Log message: Potential spiller improvement. --- Diffs of the changes: (+27 -0) README.txt | 27 +++++++++++++++++++++++++++ 1 files changed, 27 insertions(+) Index: llvm/lib/CodeGen/README.txt diff -c /dev/null llvm/lib/CodeGen/README.txt:1.1 *** /dev/null Tue Mar 20 17:22:48 2007 --- llvm/lib/CodeGen/README.txt Tue Mar 20 17:22:38 2007 *************** *** 0 **** --- 1,27 ---- + Common register allocation / spilling problem: + + mul lr, r4, lr + str lr, [sp, #+52] + ldr lr, [r1, #+32] + sxth r3, r3 + ldr r4, [sp, #+52] + mla r4, r3, lr, r4 + + can be: + + mul lr, r4, lr + mov r4, lr + str lr, [sp, #+52] + ldr lr, [r1, #+32] + sxth r3, r3 + mla r4, r3, lr, r4 + + and then "merge" mul and mov: + + mul r4, r4, lr + str lr, [sp, #+52] + ldr lr, [r1, #+32] + sxth r3, r3 + mla r4, r3, lr, r4 + + It also increase the likelyhood the store may become dead. _______________________________________________ llvm-commits mailing list llvm-commits@cs.uiuc.edu http://lists.cs.uiuc.edu/mailman/listinfo/llvm-commits
