[llvm] c259d3a - [AMDGPU] Fix for folding v2.16 literals.
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Wed Sep 9 15:39:45 PDT 2020
Author: dfukalov
Date: 2020-09-10T01:39:25+03:00
New Revision: c259d3a061c8fc0f9520208eb265d4352a0ad447
URL: https://github.com/llvm/llvm-project/commit/c259d3a061c8fc0f9520208eb265d4352a0ad447
DIFF: https://github.com/llvm/llvm-project/commit/c259d3a061c8fc0f9520208eb265d4352a0ad447.diff
LOG: [AMDGPU] Fix for folding v2.16 literals.
It was found some packed immediate operands (e.g. `<half 1.0, half 2.0>`) are
incorrectly processed so one of two packed values were lost.
Introduced new function to check immediate 32-bit operand can be folded.
Converted condition about current op_sel flags value to fall-through.
Fixes: SWDEV-247595
Reviewed By: rampitec
Differential Revision: https://reviews.llvm.org/D87158
Added:
Modified:
llvm/lib/Target/AMDGPU/SIFoldOperands.cpp
llvm/lib/Target/AMDGPU/Utils/AMDGPUBaseInfo.cpp
llvm/lib/Target/AMDGPU/Utils/AMDGPUBaseInfo.h
llvm/test/CodeGen/AMDGPU/shrink-add-sub-constant.ll
Removed:
################################################################################
diff --git a/llvm/lib/Target/AMDGPU/SIFoldOperands.cpp b/llvm/lib/Target/AMDGPU/SIFoldOperands.cpp
index 9a30d4fd6bd4..b5f6765e85ab 100644
--- a/llvm/lib/Target/AMDGPU/SIFoldOperands.cpp
+++ b/llvm/lib/Target/AMDGPU/SIFoldOperands.cpp
@@ -192,8 +192,8 @@ static bool updateOperand(FoldCandidate &Fold,
if (Fold.isImm()) {
if (MI->getDesc().TSFlags & SIInstrFlags::IsPacked &&
!(MI->getDesc().TSFlags & SIInstrFlags::IsMAI) &&
- AMDGPU::isInlinableLiteralV216(static_cast<uint16_t>(Fold.ImmToFold),
- ST.hasInv2PiInlineImm())) {
+ AMDGPU::isFoldableLiteralV216(Fold.ImmToFold,
+ ST.hasInv2PiInlineImm())) {
// Set op_sel/op_sel_hi on this operand or bail out if op_sel is
// already set.
unsigned Opcode = MI->getOpcode();
@@ -209,30 +209,30 @@ static bool updateOperand(FoldCandidate &Fold,
ModIdx = AMDGPU::getNamedOperandIdx(Opcode, ModIdx);
MachineOperand &Mod = MI->getOperand(ModIdx);
unsigned Val = Mod.getImm();
- if ((Val & SISrcMods::OP_SEL_0) || !(Val & SISrcMods::OP_SEL_1))
- return false;
- // Only apply the following transformation if that operand requries
- // a packed immediate.
- switch (TII.get(Opcode).OpInfo[OpNo].OperandType) {
- case AMDGPU::OPERAND_REG_IMM_V2FP16:
- case AMDGPU::OPERAND_REG_IMM_V2INT16:
- case AMDGPU::OPERAND_REG_INLINE_C_V2FP16:
- case AMDGPU::OPERAND_REG_INLINE_C_V2INT16:
- // If upper part is all zero we do not need op_sel_hi.
- if (!isUInt<16>(Fold.ImmToFold)) {
- if (!(Fold.ImmToFold & 0xffff)) {
- Mod.setImm(Mod.getImm() | SISrcMods::OP_SEL_0);
+ if (!(Val & SISrcMods::OP_SEL_0) && (Val & SISrcMods::OP_SEL_1)) {
+ // Only apply the following transformation if that operand requries
+ // a packed immediate.
+ switch (TII.get(Opcode).OpInfo[OpNo].OperandType) {
+ case AMDGPU::OPERAND_REG_IMM_V2FP16:
+ case AMDGPU::OPERAND_REG_IMM_V2INT16:
+ case AMDGPU::OPERAND_REG_INLINE_C_V2FP16:
+ case AMDGPU::OPERAND_REG_INLINE_C_V2INT16:
+ // If upper part is all zero we do not need op_sel_hi.
+ if (!isUInt<16>(Fold.ImmToFold)) {
+ if (!(Fold.ImmToFold & 0xffff)) {
+ Mod.setImm(Mod.getImm() | SISrcMods::OP_SEL_0);
+ Mod.setImm(Mod.getImm() & ~SISrcMods::OP_SEL_1);
+ Old.ChangeToImmediate((Fold.ImmToFold >> 16) & 0xffff);
+ return true;
+ }
Mod.setImm(Mod.getImm() & ~SISrcMods::OP_SEL_1);
- Old.ChangeToImmediate((Fold.ImmToFold >> 16) & 0xffff);
+ Old.ChangeToImmediate(Fold.ImmToFold & 0xffff);
return true;
}
- Mod.setImm(Mod.getImm() & ~SISrcMods::OP_SEL_1);
- Old.ChangeToImmediate(Fold.ImmToFold & 0xffff);
- return true;
+ break;
+ default:
+ break;
}
- break;
- default:
- break;
}
}
}
diff --git a/llvm/lib/Target/AMDGPU/Utils/AMDGPUBaseInfo.cpp b/llvm/lib/Target/AMDGPU/Utils/AMDGPUBaseInfo.cpp
index dd662d9d06f2..92cbbf336f93 100644
--- a/llvm/lib/Target/AMDGPU/Utils/AMDGPUBaseInfo.cpp
+++ b/llvm/lib/Target/AMDGPU/Utils/AMDGPUBaseInfo.cpp
@@ -1380,6 +1380,19 @@ bool isInlinableIntLiteralV216(int32_t Literal) {
return Lo16 == Hi16 && isInlinableIntLiteral(Lo16);
}
+bool isFoldableLiteralV216(int32_t Literal, bool HasInv2Pi) {
+ assert(HasInv2Pi);
+
+ int16_t Lo16 = static_cast<int16_t>(Literal);
+ if (isInt<16>(Literal) || isUInt<16>(Literal))
+ return true;
+
+ int16_t Hi16 = static_cast<int16_t>(Literal >> 16);
+ if (!(Literal & 0xffff))
+ return true;
+ return Lo16 == Hi16;
+}
+
bool isArgPassedInSGPR(const Argument *A) {
const Function *F = A->getParent();
diff --git a/llvm/lib/Target/AMDGPU/Utils/AMDGPUBaseInfo.h b/llvm/lib/Target/AMDGPU/Utils/AMDGPUBaseInfo.h
index 9c66b27733db..c5feadb98f13 100644
--- a/llvm/lib/Target/AMDGPU/Utils/AMDGPUBaseInfo.h
+++ b/llvm/lib/Target/AMDGPU/Utils/AMDGPUBaseInfo.h
@@ -693,6 +693,9 @@ bool isInlinableLiteralV216(int32_t Literal, bool HasInv2Pi);
LLVM_READNONE
bool isInlinableIntLiteralV216(int32_t Literal);
+LLVM_READNONE
+bool isFoldableLiteralV216(int32_t Literal, bool HasInv2Pi);
+
bool isArgPassedInSGPR(const Argument *Arg);
LLVM_READONLY
diff --git a/llvm/test/CodeGen/AMDGPU/shrink-add-sub-constant.ll b/llvm/test/CodeGen/AMDGPU/shrink-add-sub-constant.ll
index 1bb5b9dd4bce..3a9fe209a0ca 100644
--- a/llvm/test/CodeGen/AMDGPU/shrink-add-sub-constant.ll
+++ b/llvm/test/CodeGen/AMDGPU/shrink-add-sub-constant.ll
@@ -1026,7 +1026,7 @@ define amdgpu_kernel void @v_test_v2i16_x_sub_7_64(<2 x i16> addrspace(1)* %out,
; GFX10-NEXT: s_waitcnt lgkmcnt(0)
; GFX10-NEXT: global_load_dword v1, v0, s[2:3]
; GFX10-NEXT: s_waitcnt vmcnt(0)
-; GFX10-NEXT: v_pk_sub_i16 v1, v1, 7 op_sel_hi:[1,0]
+; GFX10-NEXT: v_pk_sub_i16 v1, v1, 0x400007
; GFX10-NEXT: global_store_dword v0, v1, s[0:1]
; GFX10-NEXT: s_endpgm
%tid = call i32 @llvm.amdgcn.workitem.id.x()
@@ -1100,7 +1100,7 @@ define amdgpu_kernel void @v_test_v2i16_x_sub_64_123(<2 x i16> addrspace(1)* %ou
; GFX10-NEXT: s_waitcnt lgkmcnt(0)
; GFX10-NEXT: global_load_dword v1, v0, s[2:3]
; GFX10-NEXT: s_waitcnt vmcnt(0)
-; GFX10-NEXT: v_pk_sub_i16 v1, v1, 64 op_sel_hi:[1,0]
+; GFX10-NEXT: v_pk_sub_i16 v1, v1, 0x7b0040
; GFX10-NEXT: global_store_dword v0, v1, s[0:1]
; GFX10-NEXT: s_endpgm
%tid = call i32 @llvm.amdgcn.workitem.id.x()
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