llvm-mirror/test/CodeGen/X86/fold-imm.ll

; RUN: llc < %s -march=x86 | grep inc
; RUN: llc < %s -march=x86 | grep add | grep 4

define i32 @test(i32 %X) nounwind {
entry:
	%0 = add i32 %X, 1
	ret i32 %0
}

define i32 @test2(i32 %X) nounwind {
entry:
	%0 = add i32 %X, 4
	ret i32 %0
}
Eliminate more uses of llvm-as and llvm-dis. llvm-svn: 81290 2009-09-09 01:54:48 +02:00			`; RUN: llc < %s -march=x86 \| grep inc`
			`; RUN: llc < %s -march=x86 \| grep add \| grep 4`
On x86 favors folding short immediate into some arithmetic operations (e.g. add, and, xor, etc.) because materializing an immediate in a register is expensive in turns of code size. e.g. movl 4(%esp), %eax addl $4, %eax is 2 bytes shorter than movl $4, %eax addl 4(%esp), %eax llvm-svn: 60139 2008-11-27 01:49:46 +01:00
			`define i32 @test(i32 %X) nounwind {`
			`entry:`
			`%0 = add i32 %X, 1`
			`ret i32 %0`
			`}`

			`define i32 @test2(i32 %X) nounwind {`
			`entry:`
			`%0 = add i32 %X, 4`
			`ret i32 %0`
			`}`