From aca75d3c08674dfa85f00100edf85c67476e333d Mon Sep 17 00:00:00 2001
From: Dhaval <dhaval@rivosinc.com>
Date: Fri, 6 Dec 2024 14:14:21 +0530
Subject: [PATCH] BaseTools: Update alignment for entry seg for Clang

It does 3 things:
1. Use separate linker file for clang vs GCC for RISCV64.
2. Use common page size instead of max page to ensure -z option align values are properly applied.
3. Enforce alignment for .entry segment as per -z option.

When we want to have -z option aligned images, clang while
alignes .text and .data segments correctly, .entry segment
is by default not aligned unless explicitly specified.
This patch makes it explicit to clang that entry seg
should also be aligned to requirements. Somehow GCC does not require such explicit
entry. Hence detachiong both ld files.

Signed-off-by: Dhaval Sharma <dhaval@rivosinc.com>
---
 BaseTools/Conf/tools_def.template |  5 +++--
 BaseTools/Scripts/ClangBase.lds   | 12 ++++++++----
 2 files changed, 11 insertions(+), 6 deletions(-)

diff --git a/BaseTools/Conf/tools_def.template b/BaseTools/Conf/tools_def.template
index 2d8c060c9c..f6bc9736b9 100755
--- a/BaseTools/Conf/tools_def.template
+++ b/BaseTools/Conf/tools_def.template
@@ -2019,7 +2019,7 @@ DEFINE CLANGDWARF_X64_PREFIX        = ENV(CLANG_BIN)
 
 # LLVM/CLANG doesn't support -n link option. So, it can't share the same IA32_X64_DLINK_COMMON flag.
 # LLVM/CLANG doesn't support common page size. So, it can't share the same GccBase.lds script.
-DEFINE CLANGDWARF_IA32_X64_DLINK_COMMON   = -nostdlib -Wl,-q,--gc-sections -z max-page-size=0x40
+DEFINE CLANGDWARF_IA32_X64_DLINK_COMMON   = -nostdlib -Wl,-q,--gc-sections -z common-page-size=0x40
 DEFINE CLANGDWARF_DLINK2_FLAGS_COMMON     = -Wl,--script=$(EDK_TOOLS_PATH)/Scripts/ClangBase.lds
 DEFINE CLANGDWARF_IA32_X64_ASLDLINK_FLAGS = DEF(CLANGDWARF_IA32_X64_DLINK_COMMON) -Wl,--defsym=PECOFF_HEADER_SIZE=0 DEF(CLANGDWARF_DLINK2_FLAGS_COMMON) -Wl,--entry,ReferenceAcpiTable -u ReferenceAcpiTable
 DEFINE CLANGDWARF_IA32_X64_DLINK_FLAGS    = DEF(CLANGDWARF_IA32_X64_DLINK_COMMON) -Wl,--entry,$(IMAGE_ENTRY_POINT) -u $(IMAGE_ENTRY_POINT) -Wl,-Map,$(DEST_DIR_DEBUG)/$(BASE_NAME).map,--whole-archive -Wl,-z,notext
@@ -2200,6 +2200,7 @@ RELEASE_CLANGDWARF_AARCH64_DLINK_FLAGS = DEF(CLANGDWARF_AARCH64_DLINK_FLAGS) -fl
 DEFINE CLANGDWARF_RISCV64_TARGET    = -target riscv64-linux-gnu
 DEFINE CLANGDWARF_RISCV64_CC_COMMON = DEF(GCC5_RISCV_ALL_CC_FLAGS) DEF(GCC5_RISCV_ALL_CC_FLAGS_WARNING_DISABLE) DEF(GCC5_RISCV_OPENSBI_TYPES) -march=DEF(GCC5_RISCV64_ARCH) -fno-builtin -fno-builtin-memcpy -fno-stack-protector -Wno-address -fno-asynchronous-unwind-tables -fno-unwind-tables -Wno-unused-but-set-variable -fpack-struct=8 -mcmodel=medany -mabi=lp64 -mno-relax
 DEFINE CLANGDWARF_RISCV64_CC_FLAGS  = DEF(CLANGDWARF_RISCV64_CC_COMMON) DEF(CLANGDWARF_RISCV64_TARGET) DEF(CLANGDWARF_WARNING_OVERRIDES)
+DEFINE CLANGDWARF_DLINK2_FLAGS_COMMON     = -Wl,--script=$(EDK_TOOLS_PATH)/Scripts/ClangBase.lds
 
 # This is similar to GCC flags but without -n
 DEFINE CLANGDWARF_RISCV64_ALL_DLINK_COMMON  = -nostdlib -Wl,-q,--gc-sections -z common-page-size=0x40
@@ -2231,7 +2232,7 @@ DEFINE CLANGDWARF_RISCV64_DLINK_FLAGS       = DEF(CLANGDWARF_RISCV64_TARGET) DEF
 *_CLANGDWARF_RISCV64_ASM_FLAGS      = DEF(GCC_ASM_FLAGS) DEF(CLANGDWARF_RISCV64_TARGET) $(PLATFORM_FLAGS) -Qunused-arguments -mabi=lp64 -mno-relax
 *_CLANGDWARF_RISCV64_DLINK_FLAGS    = DEF(CLANGDWARF_RISCV64_TARGET) DEF(GCC5_RISCV64_DLINK_FLAGS)
 *_CLANGDWARF_RISCV64_DLINK_XIPFLAGS = -z common-page-size=0x20
-*_CLANGDWARF_RISCV64_DLINK2_FLAGS   = DEF(GCC_DLINK2_FLAGS_COMMON) -Wl,--defsym=PECOFF_HEADER_SIZE=0x240
+*_CLANGDWARF_RISCV64_DLINK2_FLAGS   = DEF(CLANGDWARF_DLINK2_FLAGS_COMMON) -Wl,--defsym=PECOFF_HEADER_SIZE=0x240
 *_CLANGDWARF_RISCV64_PLATFORM_FLAGS =
 *_CLANGDWARF_RISCV64_PP_FLAGS       = DEF(GCC_PP_FLAGS) DEF(CLANGDWARF_RISCV64_TARGET) $(PLATFORM_FLAGS)
 *_CLANGDWARF_RISCV64_RC_FLAGS       = DEF(GCC_RISCV64_RC_FLAGS)
diff --git a/BaseTools/Scripts/ClangBase.lds b/BaseTools/Scripts/ClangBase.lds
index c7dcd2024a..633cdbac3b 100644
--- a/BaseTools/Scripts/ClangBase.lds
+++ b/BaseTools/Scripts/ClangBase.lds
@@ -20,7 +20,11 @@ SECTIONS {
    */
   . = PECOFF_HEADER_SIZE;
 
-  .text : ALIGN(CONSTANT(MAXPAGESIZE)) {
+  .entry ALIGN(CONSTANT(COMMONPAGESIZE)) : {
+    KEEP(*(.entry))
+  }
+
+  .text : ALIGN(CONSTANT(COMMONPAGESIZE)) {
     *(.text .text.* .stub .gnu.linkonce.t.*)
     *(.rodata .rodata.* .gnu.linkonce.r.*)
     *(.got .got.*)
@@ -42,12 +46,12 @@ SECTIONS {
    * between these sections is the same in the ELF and the PE/COFF versions of
    * this binary.
    */
-  .data ALIGN(ALIGNOF(.text)) : ALIGN(CONSTANT(MAXPAGESIZE)) {
+  .data ALIGN(ALIGNOF(.text)) : ALIGN(CONSTANT(COMMONPAGESIZE)) {
     *(.data .data.* .gnu.linkonce.d.*)
     *(.bss .bss.*)
   }
 
-  .eh_frame ALIGN(CONSTANT(MAXPAGESIZE)) : {
+  .eh_frame ALIGN(CONSTANT(COMMONPAGESIZE)) : {
     KEEP (*(.eh_frame))
   }
 
@@ -55,7 +59,7 @@ SECTIONS {
     *(.rela .rela.*)
   }
 
-  .hii : ALIGN(CONSTANT(MAXPAGESIZE)) {
+  .hii : ALIGN(CONSTANT(COMMONPAGESIZE)) {
     KEEP (*(.hii))
   }