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Commit e641e92c by Jim Stichnoth
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Subzero: Fix JumpTable lowering on x86-64.

The problem is that when switch lowering decides to use a JumpTable and the switch variable is i64 on x86-64, the lowering tries to movzx the i64 variable into an i32 variable, and the Movzx ctor asserts. This happens when translating pnacl-llc.pexe, but luckily it is also triggered in the existing adv-switch.ll test. BUG= none R=jpp@chromium.org Review URL: https://codereview.chromium.org/1743133002 .
parent b6dcf3c5
Showing with 46 additions and 32 deletions
src/IceTargetLoweringX86BaseImpl.h
...@@ -5853,7 +5853,12 @@ void TargetX86Base<TraitsType>::lowerCaseCluster(const CaseCluster &Case, ...@@ -5853,7 +5853,12 @@ void TargetX86Base<TraitsType>::lowerCaseCluster(const CaseCluster &Case,
const Type PointerType = getPointerType(); const Type PointerType = getPointerType();
if (RangeIndex->getType() != PointerType) { if (RangeIndex->getType() != PointerType) {
Index = makeReg(PointerType); Index = makeReg(PointerType);
_movzx(Index, RangeIndex); if (RangeIndex->getType() == IceType_i64) {
assert(Traits::Is64Bit);
_mov(Index, RangeIndex); // trunc
} else {
_movzx(Index, RangeIndex);
}
} else { } else {
Index = legalizeToReg(RangeIndex); Index = legalizeToReg(RangeIndex);
} }
......
tests_lit/llvm2ice_tests/adv-switch-opt.ll
; This tests the advanced lowering of switch statements. The advanced lowering ; This tests the advanced lowering of switch statements. The advanced lowering
; uses jump tables, range tests and binary search. ; uses jump tables, range tests and binary search.
; RUN: %p2i -i %s --filetype=obj --disassemble --args -O2 | FileCheck %s ; RUN: %p2i -i %s --target=x8632 --filetype=obj --disassemble --args -O2 \
; RUN: | FileCheck %s --check-prefix=CHECK --check-prefix=X8632
; RUN: %p2i -i %s --target=x8664 --filetype=obj --disassemble --args -O2 \
; RUN: | FileCheck %s --check-prefix=CHECK --check-prefix=X8664
; Dense but non-continuous ranges should be converted into a jump table. ; Dense but non-continuous ranges should be converted into a jump table.
define internal i32 @testJumpTable(i32 %a) { define internal i32 @testJumpTable(i32 %a) {
...@@ -32,8 +35,13 @@ sw.epilog: ...@@ -32,8 +35,13 @@ sw.epilog:
; CHECK: sub [[IND:[^,]+]],0x5b ; CHECK: sub [[IND:[^,]+]],0x5b
; CHECK-NEXT: cmp [[IND]],0x8 ; CHECK-NEXT: cmp [[IND]],0x8
; CHECK-NEXT: ja ; CHECK-NEXT: ja
; CHECK-NEXT: mov [[TARGET:.*]],DWORD PTR {{\[}}[[IND]]*4+0x0] {{[0-9a-f]+}}: R_386_32 .{{.*}}testJumpTable$jumptable ; X8632-NEXT: mov [[TARGET:.*]],DWORD PTR {{\[}}[[IND]]*4+0x0] {{[0-9a-f]+}}: R_386_32 .{{.*}}testJumpTable$jumptable
; CHECK-NEXT: jmp [[TARGET]] ; X8632-NEXT: jmp [[TARGET]]
; X8664-NEXT: mov {{.}}[[TARGET:.*]],DWORD PTR {{\[}}[[IND]]*4+0x0] {{[0-9a-f]+}}: R_X86_64_32S .{{.*}}testJumpTable$jumptable
; X8664-NEXT: jmp {{.}}[[TARGET]]
; Note: x86-32 may do "mov eax, [...]; jmp eax", whereas x86-64 may do
; "mov eax, [...]; jmp rax", so we assume the all characters except the first
; one in the register name will match.
; Continuous ranges which map to the same target should be grouped and ; Continuous ranges which map to the same target should be grouped and
; efficiently tested. ; efficiently tested.
...@@ -129,18 +137,18 @@ return: ...@@ -129,18 +137,18 @@ return:
ret i32 %retval.0 ret i32 %retval.0
} }
; CHECK-LABEL: testSwitchSmall64 ; CHECK-LABEL: testSwitchSmall64
; CHECK: cmp {{.*}},0x0 ; X8632: cmp {{.*}},0x0
; CHECK-NEXT: jne ; X8632-NEXT: jne
; CHECK-NEXT: cmp {{.*}},0x159 ; X8632-NEXT: cmp {{.*}},0x159
; CHECK-NEXT: jb ; X8632-NEXT: jb
; CHECK-NEXT: je ; X8632-NEXT: je
; CHECK-NEXT: cmp {{.*}},0x1c8 ; X8632-NEXT: cmp {{.*}},0x1c8
; CHECK-NEXT: je ; X8632-NEXT: je
; CHECK-NEXT: jmp ; X8632-NEXT: jmp
; CHECK-NEXT: cmp {{.*}},0x7b ; X8632-NEXT: cmp {{.*}},0x7b
; CHECK-NEXT: je ; X8632-NEXT: je
; CHECK-NEXT: cmp {{.*}},0xea ; X8632-NEXT: cmp {{.*}},0xea
; CHECK-NEXT: je ; X8632-NEXT: je
; Test for correct 64-bit lowering. ; Test for correct 64-bit lowering.
; TODO(ascull): this should generate better code like the 32-bit version ; TODO(ascull): this should generate better code like the 32-bit version
...@@ -170,22 +178,22 @@ return: ...@@ -170,22 +178,22 @@ return:
ret i32 %retval.0 ret i32 %retval.0
} }
; CHECK-LABEL: testSwitch64 ; CHECK-LABEL: testSwitch64
; CHECK: cmp {{.*}},0x7b ; X8632: cmp {{.*}},0x7b
; CHECK-NEXT: jne ; X8632-NEXT: jne
; CHECK-NEXT: cmp {{.*}},0x0 ; X8632-NEXT: cmp {{.*}},0x0
; CHECK-NEXT: je ; X8632-NEXT: je
; CHECK: cmp {{.*}},0xea ; X8632: cmp {{.*}},0xea
; CHECK-NEXT: jne ; X8632-NEXT: jne
; CHECK-NEXT: cmp {{.*}},0x0 ; X8632-NEXT: cmp {{.*}},0x0
; CHECK-NEXT: je ; X8632-NEXT: je
; CHECK: cmp {{.*}},0x159 ; X8632: cmp {{.*}},0x159
; CHECK-NEXT: jne ; X8632-NEXT: jne
; CHECK-NEXT: cmp {{.*}},0x0 ; X8632-NEXT: cmp {{.*}},0x0
; CHECK-NEXT: je ; X8632-NEXT: je
; CHECK: cmp {{.*}},0x34567890 ; X8632: cmp {{.*}},0x34567890
; CHECK-NEXT: jne ; X8632-NEXT: jne
; CHECK-NEXT: cmp {{.*}},0x12 ; X8632-NEXT: cmp {{.*}},0x12
; CHECK-NEXT: je ; X8632-NEXT: je
; Test for correct 64-bit jump table with UINT64_MAX as one of the values. ; Test for correct 64-bit jump table with UINT64_MAX as one of the values.
define internal i32 @testJumpTable64(i64 %a) { define internal i32 @testJumpTable64(i64 %a) {
...@@ -216,3 +224,4 @@ return: ...@@ -216,3 +224,4 @@ return:
; TODO(ascull): this should generate a jump table. For now, just make sure it ; TODO(ascull): this should generate a jump table. For now, just make sure it
; doesn't crash the compiler. ; doesn't crash the compiler.
; CHECK-LABEL: testJumpTable64
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