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llvm-project/llvm/test/CodeGen/X86/test-nofold.ll

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Add some tests and update an existing test to reflect recent x86 isel peeps. llvm-svn: 92509
2010-01-05 04:53:54 +08:00
; RUN: llc < %s -march=x86 -mcpu=yonah | FileCheck %s
Don't fold and's into test instructions if they have multiple uses. This compiles test-nofold.ll into: _test: movl $15, %ecx andl 4(%esp), %ecx testl %ecx, %ecx movl $42, %eax cmove %ecx, %eax ret instead of: _test: movl 4(%esp), %eax movl %eax, %ecx andl $15, %ecx testl $15, %eax movl $42, %eax cmove %ecx, %eax ret llvm-svn: 47330
2008-02-20 01:37:35 +08:00
; rdar://5752025
Add some tests and update an existing test to reflect recent x86 isel peeps. llvm-svn: 92509
2010-01-05 04:53:54 +08:00
; We want:
In the pre-RA scheduler, maintain cmp+br proximity. This is done by pushing physical register definitions close to their use, which happens to handle flag definitions if they're not glued to the branch. This seems to be generally a good thing though, so I didn't need to add a target hook yet. The primary motivation is to generate code closer to what people expect and rule out missed opportunity from enabling macro-op fusion. As a side benefit, we get several 2-5% gains on x86 benchmarks. There is one regression: SingleSource/Benchmarks/Shootout/lists slows down be -10%. But this is an independent scheduler bug that will be tracked separately. See rdar://problem/9283108. Incidentally, pre-RA scheduling is only half the solution. Fixing the later passes is tracked by: <rdar://problem/8932804> [pre-RA-sched] on x86, attempt to schedule CMP/TEST adjacent with condition jump Fixes: <rdar://problem/9262453> Scheduler unnecessary break of cmp/jump fusion llvm-svn: 129508
2011-04-14 13:15:06 +08:00
; CHECK: movl $42, %ecx
; CHECK-NEXT: movl 4(%esp), %eax
; CHECK-NEXT: andl $15, %eax
; CHECK-NEXT: cmovnel %ecx, %eax
Add some tests and update an existing test to reflect recent x86 isel peeps. llvm-svn: 92509
2010-01-05 04:53:54 +08:00
; CHECK-NEXT: ret
;
; We don't want:
; movl 4(%esp), %eax
; movl %eax, %ecx # bad: extra copy
; andl $15, %ecx
; testl $15, %eax # bad: peep obstructed
; movl $42, %eax
; cmovel %ecx, %eax
; ret
;
; We also don't want:
; movl $15, %ecx # bad: larger encoding
Don't fold and's into test instructions if they have multiple uses. This compiles test-nofold.ll into: _test: movl $15, %ecx andl 4(%esp), %ecx testl %ecx, %ecx movl $42, %eax cmove %ecx, %eax ret instead of: _test: movl 4(%esp), %eax movl %eax, %ecx andl $15, %ecx testl $15, %eax movl $42, %eax cmove %ecx, %eax ret llvm-svn: 47330
2008-02-20 01:37:35 +08:00
; andl 4(%esp), %ecx
; movl $42, %eax
Add some tests and update an existing test to reflect recent x86 isel peeps. llvm-svn: 92509
2010-01-05 04:53:54 +08:00
; cmovel %ecx, %eax
Don't fold and's into test instructions if they have multiple uses. This compiles test-nofold.ll into: _test: movl $15, %ecx andl 4(%esp), %ecx testl %ecx, %ecx movl $42, %eax cmove %ecx, %eax ret instead of: _test: movl 4(%esp), %eax movl %eax, %ecx andl $15, %ecx testl $15, %eax movl $42, %eax cmove %ecx, %eax ret llvm-svn: 47330
2008-02-20 01:37:35 +08:00
; ret
;
Add some tests and update an existing test to reflect recent x86 isel peeps. llvm-svn: 92509
2010-01-05 04:53:54 +08:00
; We also don't want:
; movl 4(%esp), %ecx
Don't fold and's into test instructions if they have multiple uses. This compiles test-nofold.ll into: _test: movl $15, %ecx andl 4(%esp), %ecx testl %ecx, %ecx movl $42, %eax cmove %ecx, %eax ret instead of: _test: movl 4(%esp), %eax movl %eax, %ecx andl $15, %ecx testl $15, %eax movl $42, %eax cmove %ecx, %eax ret llvm-svn: 47330
2008-02-20 01:37:35 +08:00
; andl $15, %ecx
Add some tests and update an existing test to reflect recent x86 isel peeps. llvm-svn: 92509
2010-01-05 04:53:54 +08:00
; testl %ecx, %ecx # bad: unnecessary test
Don't fold and's into test instructions if they have multiple uses. This compiles test-nofold.ll into: _test: movl $15, %ecx andl 4(%esp), %ecx testl %ecx, %ecx movl $42, %eax cmove %ecx, %eax ret instead of: _test: movl 4(%esp), %eax movl %eax, %ecx andl $15, %ecx testl $15, %eax movl $42, %eax cmove %ecx, %eax ret llvm-svn: 47330
2008-02-20 01:37:35 +08:00
; movl $42, %eax
Add some tests and update an existing test to reflect recent x86 isel peeps. llvm-svn: 92509
2010-01-05 04:53:54 +08:00
; cmovel %ecx, %eax
Don't fold and's into test instructions if they have multiple uses. This compiles test-nofold.ll into: _test: movl $15, %ecx andl 4(%esp), %ecx testl %ecx, %ecx movl $42, %eax cmove %ecx, %eax ret instead of: _test: movl 4(%esp), %eax movl %eax, %ecx andl $15, %ecx testl $15, %eax movl $42, %eax cmove %ecx, %eax ret llvm-svn: 47330
2008-02-20 01:37:35 +08:00
; ret
define i32 @t1(i32 %X) nounwind {
entry:
%tmp2 = and i32 %X, 15 ; <i32> [#uses=2]
%tmp4 = icmp eq i32 %tmp2, 0 ; <i1> [#uses=1]
%retval = select i1 %tmp4, i32 %tmp2, i32 42 ; <i32> [#uses=1]
ret i32 %retval
}