From 0a98bd5bb8a9b6cab765323c3a9a4000eaf13f26 Mon Sep 17 00:00:00 2001 From: Tom Stellard Date: Mon, 24 Feb 2014 18:47:58 +0000 Subject: Merging r197503, r197505, r197520: ------------------------------------------------------------------------ r197520 | dexonsmith | 2013-12-17 12:28:21 -0800 (Tue, 17 Dec 2013) | 7 lines Assert that the last operand is actually EFLAGS This is another follow-up to r197503, after a post-commit review by Andy. ------------------------------------------------------------------------ r197505 | dexonsmith | 2013-12-17 08:20:37 -0800 (Tue, 17 Dec 2013) | 6 lines Setting the CPU in the new vaargs test Trying to fix buildbots after r197503 (test passes locally). ------------------------------------------------------------------------ r197503 | dexonsmith | 2013-12-17 07:54:45 -0800 (Tue, 17 Dec 2013) | 17 lines Revert "Revert "Mark vastart_save_xmm_regs as changing EFLAGS"" This reverts commit r197481, recommiting r197469 with an extra fix. The vastart_save_xmm_regs pseudo-instruction expands to a test and a branch, so it modifies EFLAGS. Mark it so, or else the scheduler might place it in the middle of another test+branch. This fixes a bug exposed by r192750, which changed the initial scheduler to source-order as part of enabling the MI Scheduler for X86. This re-commit changes the VASTART_SAVE_XMM_REGS custom inserter not to try to save %flags, and adds a test that catches the bad behavior of r197469. ------------------------------------------------------------------------ git-svn-id: https://llvm.org/svn/llvm-project/llvm/branches/release_34@202060 91177308-0d34-0410-b5e6-96231b3b80d8 --- lib/Target/X86/X86ISelLowering.cpp | 8 +++- lib/Target/X86/X86InstrCompiler.td | 5 ++- test/CodeGen/X86/vaargs.ll | 67 +++++++++++++++++++++++++++++++++ test/CodeGen/X86/vastart-defs-eflags.ll | 23 +++++++++++ 4 files changed, 100 insertions(+), 3 deletions(-) create mode 100644 test/CodeGen/X86/vaargs.ll create mode 100644 test/CodeGen/X86/vastart-defs-eflags.ll diff --git a/lib/Target/X86/X86ISelLowering.cpp b/lib/Target/X86/X86ISelLowering.cpp index 76eeb64650..06929dd188 100644 --- a/lib/Target/X86/X86ISelLowering.cpp +++ b/lib/Target/X86/X86ISelLowering.cpp @@ -15226,9 +15226,15 @@ X86TargetLowering::EmitVAStartSaveXMMRegsWithCustomInserter( MBB->addSuccessor(EndMBB); } + // Make sure the last operand is EFLAGS, which gets clobbered by the branch + // that was just emitted, but clearly shouldn't be "saved". + assert((MI->getNumOperands() <= 3 || + !MI->getOperand(MI->getNumOperands() - 1).isReg() || + MI->getOperand(MI->getNumOperands() - 1).getReg() == X86::EFLAGS) + && "Expected last argument to be EFLAGS"); unsigned MOVOpc = Subtarget->hasFp256() ? X86::VMOVAPSmr : X86::MOVAPSmr; // In the XMM save block, save all the XMM argument registers. - for (int i = 3, e = MI->getNumOperands(); i != e; ++i) { + for (int i = 3, e = MI->getNumOperands() - 1; i != e; ++i) { int64_t Offset = (i - 3) * 16 + VarArgsFPOffset; MachineMemOperand *MMO = F->getMachineMemOperand( diff --git a/lib/Target/X86/X86InstrCompiler.td b/lib/Target/X86/X86InstrCompiler.td index 7d10b67bfe..5c8840823b 100644 --- a/lib/Target/X86/X86InstrCompiler.td +++ b/lib/Target/X86/X86InstrCompiler.td @@ -72,7 +72,7 @@ def ADJCALLSTACKUP64 : I<0, Pseudo, (outs), (ins i32imm:$amt1, i32imm:$amt2), // x86-64 va_start lowering magic. -let usesCustomInserter = 1 in { +let usesCustomInserter = 1, Defs = [EFLAGS] in { def VASTART_SAVE_XMM_REGS : I<0, Pseudo, (outs), (ins GR8:$al, @@ -81,7 +81,8 @@ def VASTART_SAVE_XMM_REGS : I<0, Pseudo, "#VASTART_SAVE_XMM_REGS $al, $regsavefi, $offset", [(X86vastart_save_xmm_regs GR8:$al, imm:$regsavefi, - imm:$offset)]>; + imm:$offset), + (implicit EFLAGS)]>; // The VAARG_64 pseudo-instruction takes the address of the va_list, // and places the address of the next argument into a register. diff --git a/test/CodeGen/X86/vaargs.ll b/test/CodeGen/X86/vaargs.ll new file mode 100644 index 0000000000..ddeb7a336d --- /dev/null +++ b/test/CodeGen/X86/vaargs.ll @@ -0,0 +1,67 @@ +; RUN: llc -mcpu=corei7-avx %s -o - | FileCheck %s --check-prefix=CHECK --check-prefix=NO-FLAGS +target datalayout = "e-p:64:64:64-i1:8:8-i8:8:8-i16:16:16-i32:32:32-i64:64:64-f32:32:32-f64:64:64-v64:64:64-v128:128:128-a0:0:64-s0:64:64-f80:128:128-n8:16:32:64-S128" +target triple = "x86_64-apple-macosx10.9.0" + +%struct.__va_list_tag = type { i32, i32, i8*, i8* } + +; Check that vastart gets the right thing. +define i32 @sum(i32 %count, ...) nounwind optsize ssp uwtable { +; CHECK: testb %al, %al +; CHECK-NEXT: je +; CHECK-NEXT: ## BB#{{[0-9]+}}: +; CHECK-NEXT: vmovaps %xmm0, 48(%rsp) +; CHECK-NEXT: vmovaps %xmm1, 64(%rsp) +; CHECK-NEXT: vmovaps %xmm2, 80(%rsp) +; CHECK-NEXT: vmovaps %xmm3, 96(%rsp) +; CHECK-NEXT: vmovaps %xmm4, 112(%rsp) +; CHECK-NEXT: vmovaps %xmm5, 128(%rsp) +; CHECK-NEXT: vmovaps %xmm6, 144(%rsp) +; CHECK-NEXT: vmovaps %xmm7, 160(%rsp) + +; Check that [EFLAGS] hasn't been pulled in. +; NO-FLAGS-NOT: %flags + + %ap = alloca [1 x %struct.__va_list_tag], align 16 + %1 = bitcast [1 x %struct.__va_list_tag]* %ap to i8* + call void @llvm.va_start(i8* %1) + %2 = icmp sgt i32 %count, 0 + br i1 %2, label %.lr.ph, label %._crit_edge + +.lr.ph: ; preds = %0 + %3 = getelementptr inbounds [1 x %struct.__va_list_tag]* %ap, i64 0, i64 0, i32 0 + %4 = getelementptr inbounds [1 x %struct.__va_list_tag]* %ap, i64 0, i64 0, i32 2 + %.pre = load i32* %3, align 16 + br label %5 + +;