Index: lib/Target/AMDGPU/AsmParser/AMDGPUAsmParser.cpp
===================================================================
--- lib/Target/AMDGPU/AsmParser/AMDGPUAsmParser.cpp
+++ lib/Target/AMDGPU/AsmParser/AMDGPUAsmParser.cpp
@@ -1754,6 +1754,11 @@
   // TODO: add syntactic sugar for 1/(2*PI)
   bool Minus = false;
   if (getLexer().getKind() == AsmToken::Minus) {
+    const AsmToken NextToken = getLexer().peekTok();
+    if (!NextToken.is(AsmToken::Integer) &&
+        !NextToken.is(AsmToken::Real)) {
+        return MatchOperand_NoMatch;
+    }
     Minus = true;
     Parser.Lex();
   }
@@ -1783,7 +1788,7 @@
     return MatchOperand_Success;
   }
   default:
-    return Minus ? MatchOperand_ParseFail : MatchOperand_NoMatch;
+    return MatchOperand_NoMatch;
   }
 }
 
Index: test/MC/AMDGPU/expressions.s
===================================================================
--- test/MC/AMDGPU/expressions.s
+++ test/MC/AMDGPU/expressions.s
@@ -46,3 +46,11 @@
 s_sub_u32 vcc_lo, vcc_lo, (BB2+4)-BB1
 // VI: s_sub_u32 vcc_lo, vcc_lo, (BB2+4)-BB1 ; encoding: [0x6a,0xff,0xea,0x80,A,A,A,A]
 // VI-NEXT: ;   fixup A - offset: 4, value: (BB2+4)-BB1, kind: FK_Data_4
+
+t=1
+s_sub_u32 s0, s0, -t
+// VI: s_sub_u32 s0, s0, -1            ; encoding: [0x00,0xc1,0x80,0x80]
+
+t=-1
+s_sub_u32 s0, s0, -t
+// VI: s_sub_u32 s0, s0, 1             ; encoding: [0x00,0x81,0x80,0x80]
Index: test/MC/AMDGPU/vop3p-err.s
===================================================================
--- test/MC/AMDGPU/vop3p-err.s
+++ test/MC/AMDGPU/vop3p-err.s
@@ -59,16 +59,16 @@
 // GFX9: :22: error: invalid operand for instruction
 v_pk_add_f16 v1, v2, abs(v3)
 
-// GFX9: :19: error: invalid operand for instruction
+// GFX9: :18: error: invalid operand for instruction
 v_pk_add_f16 v1, -v2, v3
 
-// GFX9: :23: error: invalid operand for instruction
+// GFX9: :22: error: invalid operand for instruction
 v_pk_add_f16 v1, v2, -v3
 
 // GFX9: :18: error: invalid operand for instruction
 v_pk_add_u16 v1, abs(v2), v3
 
-// GFX9: :19: error: invalid operand for instruction
+// GFX9: :18: error: invalid operand for instruction
 v_pk_add_u16 v1, -v2, v3
 
 //