DIV8r must define %AX since X86DAGToDAGISel::Select() sometimes uses it

instead of %AL/%AH.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@97006 91177308-0d34-0410-b5e6-96231b3b80d8

diff --git a/lib/Target/X86/X86InstrInfo.td b/lib/Target/X86/X86InstrInfo.td
index a6fd81f..d4ce223 100644 (file)
--- a/lib/Target/X86/X86InstrInfo.td
+++ b/lib/Target/X86/X86InstrInfo.td
@@ -1156,7 +1156,7 @@ def IMUL32m : I<0xF7, MRM5m, (outs), (ins i32mem:$src),
 } // neverHasSideEffects
 
 // unsigned division/remainder
-let Defs = [AL,AH,EFLAGS], Uses = [AX] in
+let Defs = [AX,EFLAGS], Uses = [AX] in
 def DIV8r  : I<0xF6, MRM6r, (outs),  (ins GR8:$src),    // AX/r8 = AL,AH
                "div{b}\t$src", []>;
 let Defs = [AX,DX,EFLAGS], Uses = [AX,DX] in

diff --git a/test/CodeGen/X86/2010-02-23-DIV8rDefinesAX.ll b/test/CodeGen/X86/2010-02-23-DIV8rDefinesAX.ll
new file mode 100644 (file)
index 0000000..8543c80
--- /dev/null
+++ b/test/CodeGen/X86/2010-02-23-DIV8rDefinesAX.ll
@@ -0,0 +1,20 @@
+; RUN: llc < %s
+; PR6374
+;
+; This test produces a DIV8r instruction and uses %AX instead of %AH and %AL.
+; The DIV8r must have the right imp-defs for that to work.
+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"
+target triple = "x86_64-apple-darwin10.0.0"
+
+%struct._i386_state = type { %union.anon }
+%union.anon = type { [0 x i8] }
+
+define void @i386_aam(%struct._i386_state* nocapture %cpustate) nounwind ssp {
+entry:
+  %call = tail call fastcc signext i8 @FETCH()    ; <i8> [#uses=1]
+  %rem = urem i8 0, %call                         ; <i8> [#uses=1]
+  store i8 %rem, i8* undef
+  ret void
+}
+
+declare fastcc signext i8 @FETCH() nounwind readnone ssp