- Skip instructions added in prolog. For specific targets, prolog may
insert helper function calls (e.g. _chkstk will be called when
there're more than 4K bytes allocated on stack). However, these
helpers don't use/def YMM/XMM registers.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@193261
91177308-0d34-0410-b5e6-
96231b3b80d8
bool BBHasCall = false;
for (MachineBasicBlock::iterator I = BB.begin(); I != BB.end(); ++I) {
- MachineInstr *MI = I;
DebugLoc dl = I->getDebugLoc();
+ MachineInstr *MI = I;
+
+ // Don't need to check instructions added in prolog.
+ // In prolog, special function calls may be added for specific targets
+ // (e.g. on Windows, a prolog helper '_chkstk' is called when the local
+ // variables exceed 4K bytes on stack.) These helpers won't use/def YMM/XMM
+ // registers.
+ if (MI->getFlag(MachineInstr::FrameSetup))
+ continue;
+
bool isControlFlow = MI->isCall() || MI->isReturn();
// Shortcut: don't need to check regular instructions in dirty state.
--- /dev/null
+; RUN: llc < %s -mcpu=core-avx-i -mtriple=i386-pc-win32 | FileCheck %s
+
+%struct_type = type { [64 x <8 x float>], <8 x float> }
+
+; Function Attrs: nounwind readnone
+declare i32 @llvm.x86.avx.movmsk.ps.256(<8 x float>)
+
+; Function Attrs: nounwind
+define i32 @equal(<8 x i32> %A) {
+allocas:
+ %first_alloc = alloca [64 x <8 x i32>]
+ %second_alloc = alloca %struct_type
+
+ %A1 = bitcast <8 x i32> %A to <8 x float>
+ %A2 = call i32 @llvm.x86.avx.movmsk.ps.256(<8 x float> %A1)
+ ret i32 %A2
+}
+
+; CHECK: equal
+; CHECK-NOT: vzeroupper
+; CHECK: _chkstk
+; CHECK: ret