summary | shortlog | log | commit | commitdiff | tree
raw | patch | inline | side by side (parent: 714319a)
raw | patch | inline | side by side (parent: 714319a)
author | Benjamin Kramer <benny.kra@googlemail.com> | |
Sun, 6 Oct 2013 13:48:22 +0000 (13:48 +0000) | ||
committer | Benjamin Kramer <benny.kra@googlemail.com> | |
Sun, 6 Oct 2013 13:48:22 +0000 (13:48 +0000) |
Regalloc can emit unaligned spills nowadays, but we can't fold the
spills into SSE ops if we can't guarantee alignment. PR12250.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@192064 91177308-0d34-0410-b5e6-96231b3b80d8
spills into SSE ops if we can't guarantee alignment. PR12250.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@192064 91177308-0d34-0410-b5e6-96231b3b80d8
lib/Target/X86/X86InstrInfo.cpp | patch | blob | history | |
test/CodeGen/X86/unaligned-spill-folding.ll | [new file with mode: 0644] | patch | blob |
index 277e043654e3950a939e3a39640485e939bfb0a8..6f8b0989a5f476bd1cd6ce9b03310ee30be05109 100644 (file)
const MachineFrameInfo *MFI = MF.getFrameInfo();
unsigned Size = MFI->getObjectSize(FrameIndex);
unsigned Alignment = MFI->getObjectAlignment(FrameIndex);
+ // If the function stack isn't realigned we don't want to fold instructions
+ // that need increased alignment.
+ if (!RI.needsStackRealignment(MF))
+ Alignment = std::min(Alignment, TM.getFrameLowering()->getStackAlignment());
if (Ops.size() == 2 && Ops[0] == 0 && Ops[1] == 1) {
unsigned NewOpc = 0;
unsigned RCSize = 0;
diff --git a/test/CodeGen/X86/unaligned-spill-folding.ll b/test/CodeGen/X86/unaligned-spill-folding.ll
--- /dev/null
@@ -0,0 +1,49 @@
+; RUN: llc -mtriple=i386-unknown-freebsd -mattr=sse2 -stack-alignment=4 -relocation-model=pic < %s | FileCheck %s -check-prefix=UNALIGNED
+; RUN: llc -mtriple=i386-unknown-freebsd -mattr=sse2 -stack-alignment=16 -relocation-model=pic < %s | FileCheck %s -check-prefix=ALIGNED
+; RUN: llc -mtriple=i386-unknown-freebsd -mattr=sse2 -stack-alignment=4 -force-align-stack -relocation-model=pic < %s | FileCheck %s -check-prefix=FORCEALIGNED
+
+@arr = internal unnamed_addr global [32 x i32] zeroinitializer, align 16
+
+; PR12250
+define i32 @test1() {
+vector.ph:
+ br label %vector.body
+
+vector.body:
+ %index = phi i32 [ 0, %vector.ph ], [ %index.next, %vector.body ]
+ %0 = getelementptr inbounds [32 x i32]* @arr, i32 0, i32 %index
+ %1 = bitcast i32* %0 to <4 x i32>*
+ %wide.load = load <4 x i32>* %1, align 16
+ %2 = add nsw <4 x i32> %wide.load, <i32 10, i32 10, i32 10, i32 10>
+ %3 = xor <4 x i32> %2, <i32 123345, i32 123345, i32 123345, i32 123345>
+ %4 = add nsw <4 x i32> %3, <i32 112, i32 112, i32 112, i32 112>
+ %5 = xor <4 x i32> %4, <i32 543345, i32 543345, i32 543345, i32 543345>
+ %6 = add nsw <4 x i32> %5, <i32 73, i32 73, i32 73, i32 73>
+ %7 = xor <4 x i32> %6, <i32 345987, i32 345987, i32 345987, i32 345987>
+ %8 = add nsw <4 x i32> %7, <i32 48, i32 48, i32 48, i32 48>
+ %9 = xor <4 x i32> %8, <i32 123987, i32 123987, i32 123987, i32 123987>
+ store <4 x i32> %9, <4 x i32>* %1, align 16
+ %index.next = add i32 %index, 4
+ %10 = icmp eq i32 %index.next, 32
+ br i1 %10, label %middle.block, label %vector.body
+
+middle.block:
+ ret i32 0
+
+; We can't fold the spill into a padd unless the stack is aligned. Just spilling
+; doesn't force stack realignment though
+; UNALIGNED-LABEL: @test1
+; UNALIGNED-NOT: andl $-{{..}}, %esp
+; UNALIGNED: movdqu {{.*}} # 16-byte Folded Spill
+; UNALIGNED-NOT: paddd {{.*}} # 16-byte Folded Reload
+
+; ALIGNED-LABEL: @test1
+; ALIGNED-NOT: andl $-{{..}}, %esp
+; ALIGNED: movdqa {{.*}} # 16-byte Spill
+; ALIGNED: paddd {{.*}} # 16-byte Folded Reload
+
+; FORCEALIGNED-LABEL: @test1
+; FORCEALIGNED: andl $-{{..}}, %esp
+; FORCEALIGNED: movdqa {{.*}} # 16-byte Spill
+; FORCEALIGNED: paddd {{.*}} # 16-byte Folded Reload
+}