Fix PR3391 and PR3864. Reg allocator infinite looping.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@67544 91177308-0d34-0410-b5e6-96231b3b80d8

1 files changed, 42 insertions, 0 deletions

diff --git a/test/CodeGen/X86/inline-asm-out-regs.ll b/test/CodeGen/X86/inline-asm-out-regs.ll
new file mode 100644
index 0000000..3a84bad
--- /dev/null
+++ b/test/CodeGen/X86/inline-asm-out-regs.ll
@@ -0,0 +1,42 @@
+; RUN: llvm-as < %s | llc -mtriple=i386-unknown-linux-gnu
+; XFAIL: *
+; Expected to run out of registers during allocation.
+; PR3391
+
+@pci_indirect = external global { }             ; <{ }*> [#uses=1]
+@pcibios_last_bus = external global i32         ; <i32*> [#uses=2]
+
+define void @pci_pcbios_init() nounwind section ".init.text" {
+entry:
+        br label %bb1.i
+
+bb1.i:          ; preds = %bb6.i.i, %bb1.i, %entry
+        %0 = load i32* null, align 8            ; <i32> [#uses=1]
+        %1 = icmp ugt i32 %0, 1048575           ; <i1> [#uses=1]
+        br i1 %1, label %bb2.i, label %bb1.i
+
+bb2.i:          ; preds = %bb1.i
+        %asmtmp.i.i = tail call { i32, i32, i32, i32 } asm "lcall *(%edi); cld\0A\09jc 1f\0A\09xor %ah, %ah\0A1:", "={dx},={ax},={bx},={cx},1,{di},~{dirflag},~{fpsr},~{flags},~{memory}"(i32 45313, { }* @pci_indirect) nounwind             ; <{ i32, i32, i32, i32 }> [#uses=2]
+        %asmresult2.i.i = extractvalue { i32, i32, i32, i32 } %asmtmp.i.i, 1   
+        ; <i32> [#uses=1]
+        %2 = lshr i32 %asmresult2.i.i, 8                ; <i32> [#uses=1]
+        %3 = trunc i32 %2 to i8         ; <i8> [#uses=1]
+        %4 = load i32* @pcibios_last_bus, align 4               ; <i32> [#uses=1]
+        %5 = icmp slt i32 %4, 0         ; <i1> [#uses=1]
+        br i1 %5, label %bb5.i.i, label %bb6.i.i
+
+bb5.i.i:                ; preds = %bb2.i
+        %asmresult4.i.i = extractvalue { i32, i32, i32, i32 } %asmtmp.i.i, 3   
+        ; <i32> [#uses=1]
+        %6 = and i32 %asmresult4.i.i, 255               ; <i32> [#uses=1]
+        store i32 %6, i32* @pcibios_last_bus, align 4
+        br label %bb6.i.i
+
+bb6.i.i:                ; preds = %bb5.i.i, %bb2.i
+        %7 = icmp eq i8 %3, 0           ; <i1> [#uses=1]
+        %or.cond.i.i = and i1 %7, false         ; <i1> [#uses=1]
+        br i1 %or.cond.i.i, label %bb1.i, label %bb8.i.i
+
+bb8.i.i:                ; preds = %bb6.i.i
+        unreachable
+}