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
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@129508 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/test/CodeGen/X86/2011-04-13-SchedCmpJmp.ll b/test/CodeGen/X86/2011-04-13-SchedCmpJmp.ll
new file mode 100644
index 0000000..07b1971
--- /dev/null
+++ b/test/CodeGen/X86/2011-04-13-SchedCmpJmp.ll
@@ -0,0 +1,65 @@
+; RUN: llc < %s -mtriple=x86_64-apple-darwin -mcpu=yonah | FileCheck %s
+; Reduced from JavaScriptCore
+
+%"class.JSC::CodeLocationCall" = type { [8 x i8] }
+%"class.JSC::JSGlobalData" = type { [4 x i8] }
+%"class.JSC::FunctionPtr" = type { i8* }
+%"class.JSC::Structure" = type { [4 x i8] }
+%"class.JSC::UString" = type { i8* }
+%"class.JSC::JSString" = type { [16 x i8], i32, %"class.JSC::UString", i32 }
+
+declare hidden fastcc void @_ZN3JSCL23returnToThrowTrampolineEPNS_12JSGlobalDataENS_16ReturnAddressPtrERS2_(%"class.JSC::JSGlobalData"* nocapture, i8*, %"class.JSC::FunctionPtr"* nocapture) nounwind noinline ssp
+
+; Avoid hoisting the test above loads or copies
+; CHECK: %entry
+; CHECK: cmpq
+; CHECK-NOT: mov
+; CHECK: jb
+define i32 @cti_op_eq(i8** nocapture %args) nounwind ssp {
+entry:
+ %0 = load i8** null, align 8
+ %tmp13 = bitcast i8* %0 to %"class.JSC::CodeLocationCall"*
+ %tobool.i.i.i = icmp ugt i8* undef, inttoptr (i64 281474976710655 to i8*)
+ %or.cond.i = and i1 %tobool.i.i.i, undef
+ br i1 %or.cond.i, label %if.then.i, label %if.end.i
+
+if.then.i: ; preds = %entry
+ br i1 undef, label %if.then.i.i.i, label %_ZN3JSC7JSValue19equalSlowCaseInlineEPNS_9ExecStateES0_S0_.exit
+
+if.then.i.i.i: ; preds = %if.then.i
+ %conv.i.i.i.i = trunc i64 undef to i32
+ br label %_ZN3JSC7JSValue19equalSlowCaseInlineEPNS_9ExecStateES0_S0_.exit
+
+if.end.i: ; preds = %entry
+ br i1 undef, label %land.rhs.i121.i, label %_ZNK3JSC7JSValue8isStringEv.exit122.i
+
+land.rhs.i121.i: ; preds = %if.end.i
+ %tmp.i.i117.i = load %"class.JSC::Structure"** undef, align 8
+ br label %_ZNK3JSC7JSValue8isStringEv.exit122.i
+
+_ZNK3JSC7JSValue8isStringEv.exit122.i: ; preds = %land.rhs.i121.i, %if.end.i
+ %brmerge.i = or i1 undef, false
+ %or.cond = or i1 false, %brmerge.i
+ br i1 %or.cond, label %_ZN3JSC7JSValue19equalSlowCaseInlineEPNS_9ExecStateES0_S0_.exit, label %if.then.i92.i
+
+if.then.i92.i: ; preds = %_ZNK3JSC7JSValue8isStringEv.exit122.i
+ tail call void @_ZNK3JSC8JSString11resolveRopeEPNS_9ExecStateE(%"class.JSC::JSString"* undef, %"class.JSC::CodeLocationCall"* %tmp13) nounwind
+ unreachable
+
+_ZN3JSC7JSValue19equalSlowCaseInlineEPNS_9ExecStateES0_S0_.exit: ; preds = %_ZNK3JSC7JSValue8isStringEv.exit122.i, %if.then.i.i.i, %if.then.i
+
+ %1 = load i8** undef, align 8
+ br i1 undef, label %do.end39, label %do.body27
+
+do.body27: ; preds = %_ZN3JSC7JSValue19equalSlowCaseInlineEPNS_9ExecStateES0_S0_.exit
+ %tmp30 = bitcast i8* %1 to %"class.JSC::JSGlobalData"*
+ %2 = getelementptr inbounds i8** %args, i64 -1
+ %3 = bitcast i8** %2 to %"class.JSC::FunctionPtr"*
+ tail call fastcc void @_ZN3JSCL23returnToThrowTrampolineEPNS_12JSGlobalDataENS_16ReturnAddressPtrERS2_(%"class.JSC::JSGlobalData"* %tmp30, i8* undef, %"class.JSC::FunctionPtr"* %3)
+ unreachable
+
+do.end39: ; preds = %_ZN3JSC7JSValue19equalSlowCaseInlineEPNS_9ExecStateES0_S0_.exit
+ ret i32 undef
+}
+
+declare void @_ZNK3JSC8JSString11resolveRopeEPNS_9ExecStateE(%"class.JSC::JSString"*, %"class.JSC::CodeLocationCall"*)
diff --git a/test/CodeGen/X86/lsr-loop-exit-cond.ll b/test/CodeGen/X86/lsr-loop-exit-cond.ll
index d33cc3a..938023f 100644
--- a/test/CodeGen/X86/lsr-loop-exit-cond.ll
+++ b/test/CodeGen/X86/lsr-loop-exit-cond.ll
@@ -1,4 +1,3 @@
-; XFAIL: *
; RUN: llc -march=x86-64 < %s | FileCheck %s
; CHECK: decq
diff --git a/test/CodeGen/X86/pr2659.ll b/test/CodeGen/X86/pr2659.ll
index 54d043d..ef0f9ea 100644
--- a/test/CodeGen/X86/pr2659.ll
+++ b/test/CodeGen/X86/pr2659.ll
@@ -18,7 +18,8 @@
; CHECK: movl $1
; CHECK-NOT: xorl
; CHECK-NOT: movl
-; CHECK-NEXT: je
+; CHECK-NOT: LBB
+; CHECK: je
ifthen: ; preds = %entry
ret i32 0
diff --git a/test/CodeGen/X86/tail-opts.ll b/test/CodeGen/X86/tail-opts.ll
index 424bd21..77710ad 100644
--- a/test/CodeGen/X86/tail-opts.ll
+++ b/test/CodeGen/X86/tail-opts.ll
@@ -109,15 +109,15 @@
; CHECK: dont_merge_oddly:
; CHECK-NOT: ret
-; CHECK: ucomiss %xmm1, %xmm2
+; CHECK: ucomiss %xmm{{[0-2]}}, %xmm{{[0-2]}}
; CHECK-NEXT: jbe .LBB2_3
-; CHECK-NEXT: ucomiss %xmm0, %xmm1
+; CHECK-NEXT: ucomiss %xmm{{[0-2]}}, %xmm{{[0-2]}}
; CHECK-NEXT: ja .LBB2_4
; CHECK-NEXT: .LBB2_2:
; CHECK-NEXT: movb $1, %al
; CHECK-NEXT: ret
; CHECK-NEXT: .LBB2_3:
-; CHECK-NEXT: ucomiss %xmm0, %xmm2
+; CHECK-NEXT: ucomiss %xmm{{[0-2]}}, %xmm{{[0-2]}}
; CHECK-NEXT: jbe .LBB2_2
; CHECK-NEXT: .LBB2_4:
; CHECK-NEXT: xorb %al, %al
diff --git a/test/CodeGen/X86/test-nofold.ll b/test/CodeGen/X86/test-nofold.ll
index f1063dc..97db1b3 100644
--- a/test/CodeGen/X86/test-nofold.ll
+++ b/test/CodeGen/X86/test-nofold.ll
@@ -2,10 +2,10 @@
; rdar://5752025
; We want:
-; CHECK: movl 4(%esp), %ecx
-; CHECK-NEXT: andl $15, %ecx
-; CHECK-NEXT: movl $42, %eax
-; CHECK-NEXT: cmovel %ecx, %eax
+; CHECK: movl $42, %ecx
+; CHECK-NEXT: movl 4(%esp), %eax
+; CHECK-NEXT: andl $15, %eax
+; CHECK-NEXT: cmovnel %ecx, %eax
; CHECK-NEXT: ret
;
; We don't want: