From 94670e82be07cdfe605f9391bf96acd3edb3a05e Mon Sep 17 00:00:00 2001
From: Petar Jovanovic <petar.jovanovic@imgtec.com>
Date: Tue, 9 May 2017 16:24:03 +0000
Subject: [PATCH] [mips] Impose a threshold for coercion of aggregates
Modified MipsABIInfo::classifyArgumentType so that it now coerces aggregate
structures only if the size of said aggregate is less than 16/64 bytes,
depending on the ABI.
Patch by Stefan Maksimovic.
Differential Revision: https://reviews.llvm.org/D32900
git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@302547 91177308-0d34-0410-b5e6-96231b3b80d8
---
lib/CodeGen/TargetInfo.cpp | 8 +++++++
test/CodeGen/mips-aggregate-arg.c | 38 +++++++++++++++++++++++++++++++
2 files changed, 46 insertions(+)
create mode 100644 test/CodeGen/mips-aggregate-arg.c
diff --git a/lib/CodeGen/TargetInfo.cpp b/lib/CodeGen/TargetInfo.cpp
index 4ebbef7dfb..5d3ccb86ff 100644
--- a/lib/CodeGen/TargetInfo.cpp
+++ b/lib/CodeGen/TargetInfo.cpp
@@ -6695,6 +6695,14 @@ MipsABIInfo::classifyArgumentType(QualType Ty, uint64_t &Offset) const {
return getNaturalAlignIndirect(Ty, RAA == CGCXXABI::RAA_DirectInMemory);
}
+ // Use indirect if the aggregate cannot fit into registers for
+ // passing arguments according to the ABI
+ unsigned Threshold = IsO32 ? 16 : 64;
+
+ if(getContext().getTypeSizeInChars(Ty) > CharUnits::fromQuantity(Threshold))
+ return ABIArgInfo::getIndirect(CharUnits::fromQuantity(Align), true,
+ getContext().getTypeAlign(Ty) / 8 > Align);
+
// If we have reached here, aggregates are passed directly by coercing to
// another structure type. Padding is inserted if the offset of the
// aggregate is unaligned.
diff --git a/test/CodeGen/mips-aggregate-arg.c b/test/CodeGen/mips-aggregate-arg.c
new file mode 100644
index 0000000000..b0be458ec6
--- /dev/null
+++ b/test/CodeGen/mips-aggregate-arg.c
@@ -0,0 +1,38 @@
+// RUN: %clang_cc1 -triple mipsel-unknown-linux-gnu -S -emit-llvm -o - %s | FileCheck -check-prefix=O32 %s
+// RUN: %clang_cc1 -triple mips64el-unknown-linux-gnu -S -emit-llvm -o - %s -target-abi n32 | FileCheck -check-prefix=N32-N64 %s
+// RUN: %clang_cc1 -triple mips64el-unknown-linux-gnu -S -emit-llvm -o - %s -target-abi n64 | FileCheck -check-prefix=N32-N64 %s
+
+struct t1 {
+ char t1[10];
+};
+
+struct t2 {
+ char t2[20];
+};
+
+struct t3 {
+ char t3[65];
+};
+
+extern struct t1 g1;
+extern struct t2 g2;
+extern struct t3 g3;
+extern void f1(struct t1);
+extern void f2(struct t2);
+extern void f3(struct t3);
+
+void f() {
+
+// O32: call void @f1(i32 inreg %3, i32 inreg %5, i16 inreg %7)
+// O32: call void @f2(%struct.t2* byval align 4 %tmp)
+// O32: call void @f3(%struct.t3* byval align 4 %tmp1)
+
+// N32-N64: call void @f1(i64 inreg %3, i16 inreg %5)
+// N32-N64: call void @f2(i64 inreg %9, i64 inreg %11, i32 inreg %13)
+// N32-N64: call void @f3(%struct.t3* byval align 8 %tmp)
+
+ f1(g1);
+ f2(g2);
+ f3(g3);
+}
+
--
2.40.0