From: Nick Lewycky <nicholas@mxc.ca>
Date: Thu, 30 Dec 2010 22:10:49 +0000 (+0000)
Subject: Add another non-commutable instruction that gas accepts commuted forms for.
X-Git-Url: http://demsky.eecs.uci.edu/git/?a=commitdiff_plain;h=c00210cef28b48b17408eb79e94691779da9d474;p=oota-llvm.git

Add another non-commutable instruction that gas accepts commuted forms for.
Fixes PR8861.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@122641 91177308-0d34-0410-b5e6-96231b3b80d8
---

diff --git a/lib/Target/X86/X86InstrInfo.td b/lib/Target/X86/X86InstrInfo.td
index 761e9ccb6c6..f9c0a7bbfb3 100644
--- a/lib/Target/X86/X86InstrInfo.td
+++ b/lib/Target/X86/X86InstrInfo.td
@@ -1465,14 +1465,15 @@ defm : FpUnaryAlias<"fucompi",  UCOM_FIPr>;
 
 
 // Handle "f{mulp,addp} st(0), $op" the same as "f{mulp,addp} $op", since they
-// commute.  We also allow fdivrp/fsubrp even though they don't commute, solely
-// because gas supports it.
+// commute.  We also allow fdiv[r]p/fsubrp even though they don't commute,
+// solely because gas supports it.
 def : InstAlias<"faddp %st(0), $op", (ADD_FPrST0 RST:$op)>;
 def : InstAlias<"fmulp %st(0), $op", (MUL_FPrST0 RST:$op)>;
 def : InstAlias<"fsubrp %st(0), $op", (SUB_FPrST0 RST:$op)>;
+def : InstAlias<"fdivp %st(0), $op", (DIVR_FPrST0 RST:$op)>;
 def : InstAlias<"fdivrp %st(0), $op", (DIV_FPrST0 RST:$op)>;
 
-// We accepts "fnstsw %eax" even though it only writes %ax.
+// We accept "fnstsw %eax" even though it only writes %ax.
 def : InstAlias<"fnstsw %eax", (FNSTSW8r)>;
 def : InstAlias<"fnstsw %al" , (FNSTSW8r)>;
 def : InstAlias<"fnstsw"     , (FNSTSW8r)>;
diff --git a/test/MC/X86/x86-64.s b/test/MC/X86/x86-64.s
index 5375919d55b..2eb2aded6ac 100644
--- a/test/MC/X86/x86-64.s
+++ b/test/MC/X86/x86-64.s
@@ -504,6 +504,10 @@ fdivrp %st(1), %st(0) // CHECK: encoding: [0xde,0xf9]
 fsubrp %ST(0), %ST(1) // CHECK: encoding: [0xde,0xe9]
 fsubrp %ST(1), %ST(0) // CHECK: encoding: [0xde,0xe9]
 
+// also PR8861
+fdivp %st(0), %st(1) // CHECK: encoding: [0xde,0xf1]
+fdivp %st(1), %st(0) // CHECK: encoding: [0xde,0xf1]
+
 
 movl	foo(%rip), %eax
 // CHECK: movl	foo(%rip), %eax