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llvm-project/llvm/test/CodeGen/X86/shift-combine.ll

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FileCheck-ize a test, make it more specific to directly test the shift removal desired. llvm-svn: 148213
2012-01-15 17:32:57 +08:00
; RUN: llc -march=x86 < %s | FileCheck %s
implement a readme entry, compiling the code into: _foo: movl $12, %eax andl 4(%esp), %eax movl _array(%eax), %eax ret instead of: _foo: movl 4(%esp), %eax shrl $2, %eax andl $3, %eax movl _array(,%eax,4), %eax ret As it turns out, this triggers all the time, in a wide variety of situations, for example, I see diffs like this in various programs: - movl 8(%eax), %eax - shll $2, %eax - andl $1020, %eax - movl (%esi,%eax), %eax + movzbl 8(%eax), %eax + movl (%esi,%eax,4), %eax - shll $2, %edx - andl $1020, %edx - movl (%edi,%edx), %edx + andl $255, %edx + movl (%edi,%edx,4), %edx Unfortunately, I also see stuff like this, which can be fixed in the X86 backend: - andl $85, %ebx - addl _bit_count(,%ebx,4), %ebp + shll $2, %ebx + andl $340, %ebx + addl _bit_count(%ebx), %ebp llvm-svn: 44656
2007-12-06 15:33:36 +08:00
FileCheck-ize a test, make it more specific to directly test the shift removal desired. llvm-svn: 148213
2012-01-15 17:32:57 +08:00
@array = weak global [4 x i32] zeroinitializer
define i32 @test_lshr_and(i32 %x) {
Convert CodeGen/*/*.ll tests to use the new CHECK-LABEL for easier debugging. No functionality change and all tests pass after conversion. This was done with the following sed invocation to catch label lines demarking function boundaries: sed -i '' "s/^;\( *\)\([A-Z0-9_]*\):\( *\)test\([A-Za-z0-9_-]*\):\( *\)$/;\1\2-LABEL:\3test\4:\5/g" test/CodeGen/*/*.ll which was written conservatively to avoid false positives rather than false negatives. I scanned through all the changes and everything looks correct. llvm-svn: 186258
2013-07-14 04:38:47 +08:00
; CHECK-LABEL: test_lshr_and:
FileCheck-ize a test, make it more specific to directly test the shift removal desired. llvm-svn: 148213
2012-01-15 17:32:57 +08:00
; CHECK-NOT: shrl
; CHECK: andl $12,
Relax the FileCheck assertion a bit -- all we really care about is that we're loading from the global array, not how it is spelled in the asm. This should fix the MSVC bots. llvm-svn: 148214
2012-01-15 17:38:59 +08:00
; CHECK: movl {{.*}}array{{.*}},
FileCheck-ize a test, make it more specific to directly test the shift removal desired. llvm-svn: 148213
2012-01-15 17:32:57 +08:00
; CHECK: ret
implement a readme entry, compiling the code into: _foo: movl $12, %eax andl 4(%esp), %eax movl _array(%eax), %eax ret instead of: _foo: movl 4(%esp), %eax shrl $2, %eax andl $3, %eax movl _array(,%eax,4), %eax ret As it turns out, this triggers all the time, in a wide variety of situations, for example, I see diffs like this in various programs: - movl 8(%eax), %eax - shll $2, %eax - andl $1020, %eax - movl (%esi,%eax), %eax + movzbl 8(%eax), %eax + movl (%esi,%eax,4), %eax - shll $2, %edx - andl $1020, %edx - movl (%edi,%edx), %edx + andl $255, %edx + movl (%edi,%edx,4), %edx Unfortunately, I also see stuff like this, which can be fixed in the X86 backend: - andl $85, %ebx - addl _bit_count(,%ebx,4), %ebp + shll $2, %ebx + andl $340, %ebx + addl _bit_count(%ebx), %ebp llvm-svn: 44656
2007-12-06 15:33:36 +08:00
entry:
FileCheck-ize a test, make it more specific to directly test the shift removal desired. llvm-svn: 148213
2012-01-15 17:32:57 +08:00
%tmp2 = lshr i32 %x, 2
%tmp3 = and i32 %tmp2, 3
%tmp4 = getelementptr [4 x i32]* @array, i32 0, i32 %tmp3
%tmp5 = load i32* %tmp4, align 4
ret i32 %tmp5
implement a readme entry, compiling the code into: _foo: movl $12, %eax andl 4(%esp), %eax movl _array(%eax), %eax ret instead of: _foo: movl 4(%esp), %eax shrl $2, %eax andl $3, %eax movl _array(,%eax,4), %eax ret As it turns out, this triggers all the time, in a wide variety of situations, for example, I see diffs like this in various programs: - movl 8(%eax), %eax - shll $2, %eax - andl $1020, %eax - movl (%esi,%eax), %eax + movzbl 8(%eax), %eax + movl (%esi,%eax,4), %eax - shll $2, %edx - andl $1020, %edx - movl (%edi,%edx), %edx + andl $255, %edx + movl (%edi,%edx,4), %edx Unfortunately, I also see stuff like this, which can be fixed in the X86 backend: - andl $85, %ebx - addl _bit_count(,%ebx,4), %ebp + shll $2, %ebx + andl $340, %ebx + addl _bit_count(%ebx), %ebp llvm-svn: 44656
2007-12-06 15:33:36 +08:00
}