forked from OSchip/llvm-project
624690c6b2
build vectors with i64 elements will only appear on 32b x86 before legalize. Since vector widening occurs during legalize, and produces i64 build_vector elements, the dag combiner is never run on these before legalize splits them into 32b elements. Teach the build_vector dag combine in x86 back end to recognize consecutive loads producing the low part of the vector. Convert the two uses of TLI's consecutive load recognizer to pass LoadSDNodes since that was required implicitly. Add a testcase for the transform. Old: subl $28, %esp movl 32(%esp), %eax movl 4(%eax), %ecx movl %ecx, 4(%esp) movl (%eax), %eax movl %eax, (%esp) movaps (%esp), %xmm0 pmovzxwd %xmm0, %xmm0 movl 36(%esp), %eax movaps %xmm0, (%eax) addl $28, %esp ret New: movl 4(%esp), %eax pmovzxwd (%eax), %xmm0 movl 8(%esp), %eax movaps %xmm0, (%eax) ret llvm-svn: 72957 |
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clang | ||
llvm |