[llvm-branch-commits] [llvm-branch] r258269 - Merging r258221:
Quentin Colombet via llvm-branch-commits
llvm-branch-commits at lists.llvm.org
Tue Jan 19 17:14:03 PST 2016
Author: qcolombet
Date: Tue Jan 19 19:14:03 2016
New Revision: 258269
URL: http://llvm.org/viewvc/llvm-project?rev=258269&view=rev
Log:
Merging r258221:
------------------------------------------------------------------------
r258221 | qcolombet | 2016-01-19 15:29:03 -0800 (Tue, 19 Jan 2016) | 8 lines
[X86] Do not run shrink-wrapping on function with split-stack attribute or HiPE
calling convention.
The implementation of the related callbacks in the x86 backend for such
functions are not ready to deal with a prologue block that is not the entry
block of the function.
This fixes PR26107, but the longer term solution would be to fix those callbacks.
------------------------------------------------------------------------
Modified:
llvm/branches/release_38/ (props changed)
llvm/branches/release_38/lib/Target/X86/X86FrameLowering.cpp
llvm/branches/release_38/test/CodeGen/X86/x86-shrink-wrap-unwind.ll
Propchange: llvm/branches/release_38/
------------------------------------------------------------------------------
--- svn:mergeinfo (original)
+++ svn:mergeinfo Tue Jan 19 19:14:03 2016
@@ -1,3 +1,3 @@
/llvm/branches/Apple/Pertwee:110850,110961
/llvm/branches/type-system-rewrite:133420-134817
-/llvm/trunk:155241,257645,257648,257730,257775,257791,257875,257902,257905,257925,257929-257930,257977,257979,257997,258168,258207
+/llvm/trunk:155241,257645,257648,257730,257775,257791,257875,257902,257905,257925,257929-257930,257977,257979,257997,258168,258207,258221
Modified: llvm/branches/release_38/lib/Target/X86/X86FrameLowering.cpp
URL: http://llvm.org/viewvc/llvm-project/llvm/branches/release_38/lib/Target/X86/X86FrameLowering.cpp?rev=258269&r1=258268&r2=258269&view=diff
==============================================================================
--- llvm/branches/release_38/lib/Target/X86/X86FrameLowering.cpp (original)
+++ llvm/branches/release_38/lib/Target/X86/X86FrameLowering.cpp Tue Jan 19 19:14:03 2016
@@ -2031,6 +2031,10 @@ void X86FrameLowering::adjustForSegmente
unsigned TlsReg, TlsOffset;
DebugLoc DL;
+ // To support shrink-wrapping we would need to insert the new blocks
+ // at the right place and update the branches to PrologueMBB.
+ assert(&(*MF.begin()) == &PrologueMBB && "Shrink-wrapping not supported yet");
+
unsigned ScratchReg = GetScratchRegister(Is64Bit, IsLP64, MF, true);
assert(!MF.getRegInfo().isLiveIn(ScratchReg) &&
"Scratch register is live-in");
@@ -2271,6 +2275,11 @@ void X86FrameLowering::adjustForHiPEProl
MachineFunction &MF, MachineBasicBlock &PrologueMBB) const {
MachineFrameInfo *MFI = MF.getFrameInfo();
DebugLoc DL;
+
+ // To support shrink-wrapping we would need to insert the new blocks
+ // at the right place and update the branches to PrologueMBB.
+ assert(&(*MF.begin()) == &PrologueMBB && "Shrink-wrapping not supported yet");
+
// HiPE-specific values
const unsigned HipeLeafWords = 24;
const unsigned CCRegisteredArgs = Is64Bit ? 6 : 5;
@@ -2584,7 +2593,14 @@ bool X86FrameLowering::canUseAsEpilogue(
bool X86FrameLowering::enableShrinkWrapping(const MachineFunction &MF) const {
// If we may need to emit frameless compact unwind information, give
// up as this is currently broken: PR25614.
- return MF.getFunction()->hasFnAttribute(Attribute::NoUnwind) || hasFP(MF);
+ return (MF.getFunction()->hasFnAttribute(Attribute::NoUnwind) || hasFP(MF)) &&
+ // The lowering of segmented stack and HiPE only support entry blocks
+ // as prologue blocks: PR26107.
+ // This limitation may be lifted if we fix:
+ // - adjustForSegmentedStacks
+ // - adjustForHiPEPrologue
+ MF.getFunction()->getCallingConv() != CallingConv::HiPE &&
+ !MF.shouldSplitStack();
}
MachineBasicBlock::iterator X86FrameLowering::restoreWin32EHStackPointers(
Modified: llvm/branches/release_38/test/CodeGen/X86/x86-shrink-wrap-unwind.ll
URL: http://llvm.org/viewvc/llvm-project/llvm/branches/release_38/test/CodeGen/X86/x86-shrink-wrap-unwind.ll?rev=258269&r1=258268&r2=258269&view=diff
==============================================================================
--- llvm/branches/release_38/test/CodeGen/X86/x86-shrink-wrap-unwind.ll (original)
+++ llvm/branches/release_38/test/CodeGen/X86/x86-shrink-wrap-unwind.ll Tue Jan 19 19:14:03 2016
@@ -1,11 +1,5 @@
; RUN: llc %s -o - | FileCheck %s --check-prefix=CHECK
;
-; This test checks that we do not use shrink-wrapping when
-; the function does not have any frame pointer and may unwind.
-; This is a workaround for a limitation in the emission of
-; the CFI directives, that are not correct in such case.
-; PR25614
-;
; Note: This test cannot be merged with the shrink-wrapping tests
; because the booleans set on the command line take precedence on
; the target logic that disable shrink-wrapping.
@@ -13,6 +7,12 @@ target datalayout = "e-m:o-i64:64-i128:1
target triple = "x86_64-apple-macosx"
+; This test checks that we do not use shrink-wrapping when
+; the function does not have any frame pointer and may unwind.
+; This is a workaround for a limitation in the emission of
+; the CFI directives, that are not correct in such case.
+; PR25614
+;
; No shrink-wrapping should occur here, until the CFI information are fixed.
; CHECK-LABEL: framelessUnwind:
;
@@ -151,3 +151,74 @@ false:
}
attributes #2 = { "no-frame-pointer-elim"="false" nounwind }
+
+
+; Check that we generate correct code for segmented stack.
+; We used to emit the code at the entry point of the function
+; instead of just before the prologue.
+; For now, shrink-wrapping is disabled on segmented stack functions: PR26107.
+;
+; CHECK-LABEL: segmentedStack:
+; CHECK: cmpq
+; CHECK-NEXT: ja [[ENTRY_LABEL:LBB[0-9_]+]]
+;
+; CHECK: callq ___morestack
+; CHECK-NEXT: retq
+;
+; CHECK: [[ENTRY_LABEL]]:
+; Prologue
+; CHECK: push
+;
+; In PR26107, we use to drop these two basic blocks, because
+; the segmentedStack entry block was jumping directly to
+; the place where the prologue is actually needed, which is
+; the call to memcmp.
+; Then, those two basic blocks did not have any predecessors
+; anymore and were removed.
+;
+; Check if vk1 is null
+; CHECK: testq %rdi, %rdi
+; CHECK-NEXT: je [[STRINGS_EQUAL:LBB[0-9_]+]]
+;
+; Check if vk2 is null
+; CHECK: testq %rsi, %rsi
+; CHECK-NEXT: je [[STRINGS_EQUAL]]
+;
+; CHECK: [[STRINGS_EQUAL]]
+; CHECK-NEXT: popq
+define zeroext i1 @segmentedStack(i8* readonly %vk1, i8* readonly %vk2, i64 %key_size) #5 {
+entry:
+ %cmp.i = icmp eq i8* %vk1, null
+ %cmp1.i = icmp eq i8* %vk2, null
+ %brmerge.i = or i1 %cmp.i, %cmp1.i
+ %cmp1.mux.i = and i1 %cmp.i, %cmp1.i
+ br i1 %brmerge.i, label %__go_ptr_strings_equal.exit, label %if.end4.i
+
+if.end4.i: ; preds = %entry
+ %tmp = getelementptr inbounds i8, i8* %vk1, i64 8
+ %tmp1 = bitcast i8* %tmp to i64*
+ %tmp2 = load i64, i64* %tmp1, align 8
+ %tmp3 = getelementptr inbounds i8, i8* %vk2, i64 8
+ %tmp4 = bitcast i8* %tmp3 to i64*
+ %tmp5 = load i64, i64* %tmp4, align 8
+ %cmp.i.i = icmp eq i64 %tmp2, %tmp5
+ br i1 %cmp.i.i, label %land.rhs.i.i, label %__go_ptr_strings_equal.exit
+
+land.rhs.i.i: ; preds = %if.end4.i
+ %tmp6 = bitcast i8* %vk2 to i8**
+ %tmp7 = load i8*, i8** %tmp6, align 8
+ %tmp8 = bitcast i8* %vk1 to i8**
+ %tmp9 = load i8*, i8** %tmp8, align 8
+ %call.i.i = tail call i32 @memcmp(i8* %tmp9, i8* %tmp7, i64 %tmp2) #5
+ %cmp4.i.i = icmp eq i32 %call.i.i, 0
+ br label %__go_ptr_strings_equal.exit
+
+__go_ptr_strings_equal.exit: ; preds = %land.rhs.i.i, %if.end4.i, %entry
+ %retval.0.i = phi i1 [ %cmp1.mux.i, %entry ], [ false, %if.end4.i ], [ %cmp4.i.i, %land.rhs.i.i ]
+ ret i1 %retval.0.i
+}
+
+; Function Attrs: nounwind readonly
+declare i32 @memcmp(i8* nocapture, i8* nocapture, i64) #5
+
+attributes #5 = { nounwind readonly ssp uwtable "split-stack" }
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