[AMDGPU] Drop 16 bit subreg suffixes on print

We do not want to break asm syntax. These suffixes are
quite useful for debugging, so add an option to print
them. Right now it is NFC.

Differential Revision: https://reviews.llvm.org/D79435

diff --git a/llvm/lib/Target/AMDGPU/MCTargetDesc/AMDGPUInstPrinter.cpp b/llvm/lib/Target/AMDGPU/MCTargetDesc/AMDGPUInstPrinter.cpp
index 36a20fb..43bd8d1 100644 (file)
--- a/llvm/lib/Target/AMDGPU/MCTargetDesc/AMDGPUInstPrinter.cpp
+++ b/llvm/lib/Target/AMDGPU/MCTargetDesc/AMDGPUInstPrinter.cpp
@@ -26,6 +26,12 @@
 using namespace llvm;
 using namespace llvm::AMDGPU;
 
+static cl::opt<bool> Keep16BitSuffixes(
+  "amdgpu-keep-16-bit-reg-suffixes",
+  cl::desc("Keep .l and .h suffixes in asm for debugging purposes"),
+  cl::init(false),
+  cl::ReallyHidden);
+
 void AMDGPUInstPrinter::printRegName(raw_ostream &OS, unsigned RegNo) const {
   // FIXME: The current implementation of
   // AsmParser::parseRegisterOrRegisterNumber in MC implies we either emit this
@@ -317,7 +323,12 @@ void AMDGPUInstPrinter::printRegOperand(unsigned RegNo, raw_ostream &O,
   }
 #endif
 
-  O << getRegisterName(RegNo);
+  StringRef RegName(getRegisterName(RegNo));
+  if (!Keep16BitSuffixes)
+    if (!RegName.consume_back(".l"))
+      RegName.consume_back(".h");
+
+  O << RegName;
 }
 
 void AMDGPUInstPrinter::printVOPDst(const MCInst *MI, unsigned OpNo,

diff --git a/llvm/test/CodeGen/AMDGPU/lo16-hi16-illegal-copy.mir b/llvm/test/CodeGen/AMDGPU/lo16-hi16-illegal-copy.mir
index 7ca9106..c8d5265 100644 (file)
--- a/llvm/test/CodeGen/AMDGPU/lo16-hi16-illegal-copy.mir
+++ b/llvm/test/CodeGen/AMDGPU/lo16-hi16-illegal-copy.mir
@@ -1,7 +1,7 @@
-# RUN: not llc -march=amdgcn -mcpu=gfx802 -start-before postrapseudos -asm-verbose=0 -verify-machineinstrs %s -o - 2>&1 | FileCheck -check-prefixes=ERR,GFX8-ERR %s
-# RUN: not llc -march=amdgcn -mcpu=gfx802 -start-before postrapseudos -asm-verbose=0 -verify-machineinstrs %s -o - 2>&1 | FileCheck -check-prefix=GCN %s
-# RUN: not llc -march=amdgcn -mcpu=gfx900 -start-before postrapseudos -asm-verbose=0 -verify-machineinstrs %s -o - 2>&1 | FileCheck -check-prefix=ERR %s
-# RUN: not llc -march=amdgcn -mcpu=gfx900 -start-before postrapseudos -asm-verbose=0 -verify-machineinstrs %s -o - 2>&1 | FileCheck -check-prefixes=GCN,GFX9 %s
+# RUN: not llc -march=amdgcn -mcpu=gfx802 -start-before postrapseudos -asm-verbose=0 -amdgpu-keep-16-bit-reg-suffixes -verify-machineinstrs %s -o - 2>&1 | FileCheck -check-prefixes=ERR,GFX8-ERR %s
+# RUN: not llc -march=amdgcn -mcpu=gfx802 -start-before postrapseudos -asm-verbose=0 -amdgpu-keep-16-bit-reg-suffixes -verify-machineinstrs %s -o - 2>&1 | FileCheck -check-prefix=GCN %s
+# RUN: not llc -march=amdgcn -mcpu=gfx900 -start-before postrapseudos -asm-verbose=0 -amdgpu-keep-16-bit-reg-suffixes -verify-machineinstrs %s -o - 2>&1 | FileCheck -check-prefix=ERR %s
+# RUN: not llc -march=amdgcn -mcpu=gfx900 -start-before postrapseudos -asm-verbose=0 -amdgpu-keep-16-bit-reg-suffixes -verify-machineinstrs %s -o - 2>&1 | FileCheck -check-prefixes=GCN,GFX9 %s
 
 # Note: GFX8 did not allow SDWA SGPR sources. Therefor no HI16 subregs can be used there.