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git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@42607 91177308-0d34-0410-b5e6-96231b3b80d8
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@ -1362,3 +1362,43 @@ _foo:
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//===---------------------------------------------------------------------===//
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//===---------------------------------------------------------------------===//
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We compile this:
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void compare (long long foo) {
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if (foo < 4294967297LL)
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abort();
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}
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to:
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_compare:
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subl $12, %esp
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cmpl $0, 16(%esp)
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setne %al
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movzbw %al, %ax
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cmpl $1, 20(%esp)
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setg %cl
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movzbw %cl, %cx
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cmove %ax, %cx
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movw %cx, %ax
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testb $1, %al
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je LBB1_2 # cond_true
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(also really horrible code on ppc). This is due to the expand code for 64-bit
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compares. GCC produces multiple branches, which is much nicer:
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_compare:
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pushl %ebp
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movl %esp, %ebp
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subl $8, %esp
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movl 8(%ebp), %eax
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movl 12(%ebp), %edx
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subl $1, %edx
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jg L5
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L7:
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jl L4
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cmpl $0, %eax
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jbe L4
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L5:
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//===---------------------------------------------------------------------===//
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