llvm-6502/test/CodeGen/X86/fold-imm.ll

; RUN: llc < %s -march=x86 | FileCheck %s

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

; CHECK: test
; CHECK: inc
; CHECK: ret

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

; CHECK: test2
; CHECK: {{add.*4.*$}}
; CHECK: ret
Rewrite X86 codegen regression test with FileCheck git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@180776 91177308-0d34-0410-b5e6-96231b3b80d8 2013-04-30 07:51:08 +00:00			`; RUN: llc < %s -march=x86 \| FileCheck %s`
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 git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@60139 91177308-0d34-0410-b5e6-96231b3b80d8 2008-11-27 00:49:46 +00:00
			`define i32 @test(i32 %X) nounwind {`
			`entry:`
			`%0 = add i32 %X, 1`
			`ret i32 %0`
			`}`

Rewrite X86 codegen regression test with FileCheck git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@180776 91177308-0d34-0410-b5e6-96231b3b80d8 2013-04-30 07:51:08 +00:00			`; CHECK: test`
			`; CHECK: inc`
			`; CHECK: ret`

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 $4, %eax addl 4(%esp), %eax git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@60139 91177308-0d34-0410-b5e6-96231b3b80d8 2008-11-27 00:49:46 +00:00			`define i32 @test2(i32 %X) nounwind {`
			`entry:`
			`%0 = add i32 %X, 4`
			`ret i32 %0`
			`}`
Rewrite X86 codegen regression test with FileCheck git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@180776 91177308-0d34-0410-b5e6-96231b3b80d8 2013-04-30 07:51:08 +00:00
			`; CHECK: test2`
			`; CHECK: {{add.4.$}}`
			`; CHECK: ret`